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Briggs 18 HP Hard to Start
#1
B
bk10s
B
bk10s
Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#2
I
ILENGINE
I
ILENGINE
Choke not closing all the way or staying shut while cranking. And depending on temperature where you are it may be temp related and some engines just don't like cold weather.
#3
doug9694
doug9694
If it ctanks slow and hard then check the decompression system. If extra fast then valves or blown head gasket likely.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#4
D
dwzkd
D
dwzkd
Check the bottom of the carburetor to see if the bowl is leaking. If it is leaking, the bowl can drain to dry over a few days. Once you get it started, it will run and start fine until it sits long enough for the carb to drain. If it still starts hard after getting it running, then this is not likely it.
If leaking, you can try to snug up the nut (or solenoid if it has one instead of nut). If this doesn't fix it, replace the washer between the bowl and nut...
Good luck.
If leaking, you can try to snug up the nut (or solenoid if it has one instead of nut). If this doesn't fix it, replace the washer between the bowl and nut...
Good luck.
#5
B
bk10s
B
bk10s
Thank you for these ideas to start! Re-checked valves yesterday. It is 3 degrees here in WI with the wind chill!
#6
B
bk10s
B
bk10s
SOLVED! Clogged fuel line from the tank to the filter. Amazing how easily this thing starts when it has gas!!!
#7
L
laurin800
L
laurin800
Bingo!If it ctanks slow and hard then check the decompression system. If extra fast then valves or blown head gasket likely.
#8
grumpyunk
grumpyunk
If is has a clogged fuel line, preventing the flow of fuel for starting at LOW rpms... how does a clogged fuel line feed the engine when it is running at HIGH rpms? The fuel demand increases with engine rpm, and cranking is low rpm, and thus low demand.
If you have a shutoff valve, that may explain, but if it is a straight through fuel line, then something else is going on.
tom
If you have a shutoff valve, that may explain, but if it is a straight through fuel line, then something else is going on.
tom
#9
B
bk10s
B
bk10s
When a took the fuel line off on the tank side of the filter, hardly any fuel came out. I blew out the line/backwards to tank and gas came gushing out (gravity). I put on a new filter and it started in about 1/2 a crank. Go figure. This engine has a fuel pump.
#10
B
bk10s
B
bk10s
Well.....Wishful thinking. Went out tonight in the -20 wind chill and.......Cranked forever and took forever to "catch". Back to the drawing board..Grrr
#11
grumpyunk
grumpyunk
The fuel outlet inside the tank is getting clogged as the fuel falls into the tube leading to the fuel line. You may be able to remove the outlet(or not, depending on design) and clean up the schmuz, or will have to see if you can flush it out after removing the tank so you can position it to allow the stuff to get out with the flush.
tom
tom
#12
B
bk10s
B
bk10s
Update: Removed the fenders and the tank. Tank was surprisingly clean (my wife was not too happy with the gas smell in the house from bringing the tank through to the basement!). Washed it out anyway. Tube and elbow clear. Maybe the fuel pump?
#13
grumpyunk
grumpyunk
I have had fuel lines that looked perfect fail to flow reasonably. The fuel over time had destroyed at least partially the inner surface and turned it into a maze. Fuel would not flow freely(gravity) through the line. You could check for gravity flow from the tank to the pump/filter, and then from there to the filter/pump, depending on the sequence. If all flows well, and the line from the pump to the carb inlet flows well, all that's left is the small volume of the inlet, and the pump. IOW, check it for flow or being able to blow through it a section at a time. Some pumps will allow slow flow via gravity if there is any height difference from tank outlet to the pump outlet as the little valves are not perfect and may allow seepage.
tom
tom
#14
B
bk10s
B
bk10s
Going to put it back together with a new fuel line from tank to filter, and see where it's at.
#15
I
irineroger
I
irineroger
Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#16
I
irineroger
I
irineroger
I took out one plug and started it on one plug, let it run for a while then put that one back in and take the other one out, it spins like it should on one plug, after both are warmed up replace the other plug , it should start within one or two turns then. I had some help from up above!Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#17
mechanizm
mechanizm
there's an easy test. squirt some gas in the carb when cold and if it starts right up then you aren't getting enough gas. if this has a vacuum operated fuel pump, squirt the hoses where they connect to the pump with a little fuel / 2stroke oil mix. sometimes they suck air and even a little bit will keep it from pumping enough into your carb. It seals minor vacuum leaks. Most of y'all are over-thinking this problem.
Also, because of EPA the carbs run LEAN so any slight issue with the fuel pump will cause a hard-start problem. the reason it runs great after it starts is because it's creating more vacuum at the pump, overcoming the vacuum leak.
Also, because of EPA the carbs run LEAN so any slight issue with the fuel pump will cause a hard-start problem. the reason it runs great after it starts is because it's creating more vacuum at the pump, overcoming the vacuum leak.
#18
G
Gord Baker
G
Gord Baker
I don't know what a 350777 is but if it has an electric solenoid fuel shut off, be sure it is working. You should be able to hear it click when you turn ignition to ON. Check the multiwire connector(s) near the switch. Disconnect and clean them with Electronic cleaner and put back together tightly. Replace Fuel Filter and always strain your fuel.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#19
R
RestoGuy
R
RestoGuy
If you blew the line back in the tank you might have blown whatever junk that plugged the system right back in the tank...or...the tank needs a good cleaning. Drain and flush the tank...new filter and try again. Drain the fuel bowl and blow out main jet at the same time. You might be very close to a fix.
#20
N
nettles.w
N
nettles.w
I had the same problem for a few years. Finally, when I retired and got time to tinker with it, I ended up gutting the vacuum powered fuel pump and replacing it with a generic electric powered replacement. Problem solved. Starts first time, every time.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#21
T
TobyU
T
TobyU
Either start some gas or carb cleaner into the intake when it won't start or hold your hand over the intake after you remove air filter to block off all air going in.
If it starts up in 2-3 revolutions, you suspect choke not shutting all the way or not enough fuel on its own.
If choke is closing all the way then pop fuel line off at carb and crank to see if fuel pump is pumping fuel out. It should blub blub blub out as it cranks.
If good there, then the less likely things are fuel solenoid acting up or leaking fuel slightly or bowl leaking so as to lower level in carb bowl and it takes all that cranking for pump to fill the bowl back up enough to start
If it runs fine under load then it's unlikely to be a fuel pump or restricted fuel line or tank UNLESS it's intermittent as those can come and go.
If it starts up in 2-3 revolutions, you suspect choke not shutting all the way or not enough fuel on its own.
If choke is closing all the way then pop fuel line off at carb and crank to see if fuel pump is pumping fuel out. It should blub blub blub out as it cranks.
If good there, then the less likely things are fuel solenoid acting up or leaking fuel slightly or bowl leaking so as to lower level in carb bowl and it takes all that cranking for pump to fill the bowl back up enough to start
If it runs fine under load then it's unlikely to be a fuel pump or restricted fuel line or tank UNLESS it's intermittent as those can come and go.
#22
T
TobyU
T
TobyU
Also, get out of the habit of suspecting and adjusting valves.
Just not that critical on these and unless you take rockers off and tighten rocker arm stud, all the wrenching will cause one to loosen up and then it will bend a pushrod and but run ...WAIT that's on the Single cyl ones
The twins are more forgiving a they have the nut adjuster at the pushrod tip of rocker and not in the middle on stud.
Regardless, when you first check a Briggs ohv valves (if you're the first in there) they will be REALLY out of spec.
Really loose.
Once you set them, they will move be that out again as they don't get out much in their own and most all the wear is from the early break in hours and slows to near nothing after that.
When the valves are needing adj esp on a single, it will be hard to spin over. Like a week batt or starter. Many batts and starters have been replaced because of this with no improvement.
It's like it starts to spin and then hits arl rubber wall and stops and bounces back a hair.
When this happens (singles esp) you HOPE to find the valves out and not a busted ACR. I am SO Happy when I see that valve "bump" back open.
Just not that critical on these and unless you take rockers off and tighten rocker arm stud, all the wrenching will cause one to loosen up and then it will bend a pushrod and but run ...WAIT that's on the Single cyl ones
The twins are more forgiving a they have the nut adjuster at the pushrod tip of rocker and not in the middle on stud.
Regardless, when you first check a Briggs ohv valves (if you're the first in there) they will be REALLY out of spec.
Really loose.
Once you set them, they will move be that out again as they don't get out much in their own and most all the wear is from the early break in hours and slows to near nothing after that.
When the valves are needing adj esp on a single, it will be hard to spin over. Like a week batt or starter. Many batts and starters have been replaced because of this with no improvement.
It's like it starts to spin and then hits arl rubber wall and stops and bounces back a hair.
When this happens (singles esp) you HOPE to find the valves out and not a busted ACR. I am SO Happy when I see that valve "bump" back open.
#23
VRR.DYNDNS>BIZ
VRR.DYNDNS>BIZ
search for about 4 replies about a hard to start that I replied the fuel solenoid will not retract under 12 volts when cranking.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#25
goodO1boydws
goodO1boydws
Just a thought here, but have you tried checking for spark while its cranking? You might be surprised at what you find.
My rider was getting ornery and it was taking a long time cranking to get the engine to catch. I do regular maintenance, changing the oil and filter, checking fuel and air filters, and checking/cleaning the plugs much more often than usual, (because the engine is using oil). Did that all again-no difference.
Then i was checking for spark and noticed that when it wouldn't start there was no spark, but the spark was fine once itwas running.
So I checked the magneto's air gap, and it was a tiny bit off, so I adjusted that. Still no difference in starting, and the same pattern of no spark when cranking, but ok whem running. I picked up a "used but good" magneto and swapped that one in. Same thing was happening at cranking speed no spark, but fine once running . I figured the magneto was as bad as mine, returned it for another one. Same thing.
Hmmmmmm. What are the odds 3 magnetos are all bad in exactly this same way?
So I figured that it was most likely something else. But what to check next? I'd replaced the starter solenoid only a year previously, and the ignitionn switch at that same time. The power and ground wires were clean and tight and the battery was up to snuff too.
i didn't want to try the carburetor yet so that the starter as a possibility.
Since starters are available from sources other than Briggs now,(and their price has dropped like a rock) i ordered one. This is the third starter thar's been on the engine, along with a couple more starter gear changes. According to the engine parts list the first 2 were the correct starters for that engine in that application.
My engine is an 18.5 hp horizontal twin and I found out that there are 3 different length starters that COULD be used, one of which is at least a half inch longer than the original, so THIS time i ordered the longest one. Once installed the engine cranked over faster than it EVER had before-even when brand new. I was shocked at how much faster.
After installation of the longer starter it started very easily too- in a second or less, compared to 20-30 seconds or more of cranking before it was in..
This was without changing ANYTHING else besides what had already been done.
So, after doing some research, here's the poop.
On many Briggs engines, the magneto will not produce ANY spark below a certain cranking rpm.
Not just a WEAKER spark-none whatsoever.
Depending on the ambient temp, and other factors, such as battery strength, ENGINE OIL WEIGHT, and what starter is installed, its possible that an engine may be cranking over JUST SLIGHTLY below that needed for the magneto to fire (maybe only 25rpm too slowly)-until you're cranked it over long enough for the engine's internal friction to begin to decrease as it goes through more revolutions, after which it spins over just a LITTLE bit faster, but its enough to be above the rpm needed for the magneto to fire. It's also more liable to start quicker in warm weather-but many engines are-for any of several reasons.
My rider was getting ornery and it was taking a long time cranking to get the engine to catch. I do regular maintenance, changing the oil and filter, checking fuel and air filters, and checking/cleaning the plugs much more often than usual, (because the engine is using oil). Did that all again-no difference.
Then i was checking for spark and noticed that when it wouldn't start there was no spark, but the spark was fine once itwas running.
So I checked the magneto's air gap, and it was a tiny bit off, so I adjusted that. Still no difference in starting, and the same pattern of no spark when cranking, but ok whem running. I picked up a "used but good" magneto and swapped that one in. Same thing was happening at cranking speed no spark, but fine once running . I figured the magneto was as bad as mine, returned it for another one. Same thing.
Hmmmmmm. What are the odds 3 magnetos are all bad in exactly this same way?
So I figured that it was most likely something else. But what to check next? I'd replaced the starter solenoid only a year previously, and the ignitionn switch at that same time. The power and ground wires were clean and tight and the battery was up to snuff too.
i didn't want to try the carburetor yet so that the starter as a possibility.
Since starters are available from sources other than Briggs now,(and their price has dropped like a rock) i ordered one. This is the third starter thar's been on the engine, along with a couple more starter gear changes. According to the engine parts list the first 2 were the correct starters for that engine in that application.
My engine is an 18.5 hp horizontal twin and I found out that there are 3 different length starters that COULD be used, one of which is at least a half inch longer than the original, so THIS time i ordered the longest one. Once installed the engine cranked over faster than it EVER had before-even when brand new. I was shocked at how much faster.
After installation of the longer starter it started very easily too- in a second or less, compared to 20-30 seconds or more of cranking before it was in..
This was without changing ANYTHING else besides what had already been done.
So, after doing some research, here's the poop.
On many Briggs engines, the magneto will not produce ANY spark below a certain cranking rpm.
Not just a WEAKER spark-none whatsoever.
Depending on the ambient temp, and other factors, such as battery strength, ENGINE OIL WEIGHT, and what starter is installed, its possible that an engine may be cranking over JUST SLIGHTLY below that needed for the magneto to fire (maybe only 25rpm too slowly)-until you're cranked it over long enough for the engine's internal friction to begin to decrease as it goes through more revolutions, after which it spins over just a LITTLE bit faster, but its enough to be above the rpm needed for the magneto to fire. It's also more liable to start quicker in warm weather-but many engines are-for any of several reasons.
#26
A
Alton R
I have seen engines that the fuel tank cap was stopped up not letting it vent properly.
A
Alton R
Just wondering if you have a vacuum leak. My mower is doing the same thing. I've already had one vacuum leak. I'm just wondering if your engine is a twen cylinder. You know a vacuum leak would memic the same symptoms as a choke not being fully closed. My engine is a 20 hp onan.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
I have seen engines that the fuel tank cap was stopped up not letting it vent properly.
#27
B
bk10s
B
bk10s
You may be on to something here. When I ran out of battery and hooked up my charger to try to start, the engine turned over faster and started quickly.Just a thought here, but have you tried checking for spark while its cranking? You might be surprised at what you find.
My rider was getting ornery and it was taking a long time cranking to get the engine to catch. I do regular maintenance, changing the oil and filter, checking fuel and air filters, and checking/cleaning the plugs much more often than usual, (because the engine is using oil). Did that all again-no difference.
Then i was checking for spark and noticed that when it wouldn't start there was no spark, but the spark was fine once itwas running.
So I checked the magneto's air gap, and it was a tiny bit off, so I adjusted that. Still no difference in starting, and the same pattern of no spark when cranking, but ok whem running. I picked up a "used but good" magneto and swapped that one in. Same thing was happening at cranking speed no spark, but fine once running . I figured the magneto was as bad as mine, returned it for another one. Same thing.
Hmmmmmm. What are the odds 3 magnetos are all bad in exactly this same way?
So I figured that it was most likely something else. But what to check next? I'd replaced the starter solenoid only a year previously, and the ignitionn switch at that same time. The power and ground wires were clean and tight and the battery was up to snuff too.
i didn't want to try the carburetor yet so that the starter as a possibility.
Since starters are available from sources other than Briggs now,(and their price has dropped like a rock) i ordered one. This is the third starter thar's been on the engine, along with a couple more starter gear changes. According to the engine parts list the first 2 were the correct starters for that engine in that application.
My engine is an 18.5 hp horizontal twin and I found out that there are 3 different length starters that COULD be used, one of which is at least a half inch longer than the original, so THIS time i ordered the longest one. Once installed the engine cranked over faster than it EVER had before-even when brand new. I was shocked at how much faster.
After installation of the longer starter it started very easily too- in a second or less, compared to 20-30 seconds or more of cranking before it was in..
This was without changing ANYTHING else besides what had already been done.
So, after doing some research, here's the poop.
On many Briggs engines, the magneto will not produce ANY spark below a certain cranking rpm.
Not just a WEAKER spark-none whatsoever.
Depending on the ambient temp, and other factors, such as battery strength, ENGINE OIL WEIGHT, and what starter is installed, its possible that an engine may be cranking over JUST SLIGHTLY below that needed for the magneto to fire (maybe only 25rpm too slowly)-until you're cranked it over long enough for the engine's internal friction to begin to decrease as it goes through more revolutions, after which it spins over just a LITTLE bit faster, but its enough to be above the rpm needed for the magneto to fire. It's also more liable to start quicker in warm weather-but many engines are-for any of several reasons.
#28
B
bk10s
B
bk10s
I have tried with the cap off. Where would I look for a vacuum leak? Valve cover gaskets, and possibly the pump not getting good vacuum?Just wondering if you have a vacuum leak. My mower is doing the same thing. I've already had one vacuum leak. I'm just wondering if your engine is a twen cylinder. You know a vacuum leak would memic the same symptoms as a choke not being fully closed. My engine is a 20 hp onan.
I have seen engines that the fuel tank cap was stopped up not letting it vent properly.
#29
S
Sherman Anderson
S
Sherman Anderson
Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#30
P
PLC
P
PLC
ILENGINE has the right idea. I have a V twin that would crank and crank and crank. My repair guy told me that before I bring it in, I should check the cable adjustment to make sure it closes completely. When I checked the choke wasn't closing totally. There was a minimal adjustment needed to get it completely closed. Started immediately when I tried it after adjustment. I couldn't believe how little adjustment made such a difference.
#31
mechanizm
mechanizm
it's a minor air leak in the carb fuel line connections. AGAIN: I squirted my line connections with oil/gas mix and PROBLEM SOLVED.
#32
T
TobyU
T
TobyU
We have touched on several times in this thread, it is more than likely not getting enough fuel or not being enriched enough by the choke when it's cold.
Having said that, I will say that the horizontally opposed twins can often be slow crankers but the coil system on these engines is pretty strong and even spitting one by hand will spark a spark plug so if it's turning over and spending the engine it probably has enough spark to run so I'm still guessing it's a fuel or enriching problem.
The answer to the fix is to find out why it's not getting enough fuel up into the throat of the carburetor when it cranks over.
This is why you start by checking the choke butterfly.
It's not common on these particular engines but these engines are also extremely old at this point and it would be rare for one this old to have not had throttle cable removed, replaced, carburetor off, etc or cable and levers and stuff just move around a little bit over the years so it's not pushing the choke butterfly closed far enough.
There was a whole rash of Kohler single courage engines a few years back coming from the factory with the chokes not adjusted to close far enough. Fix was as easy as using a torx driver on a purple paint marked screw to increase the choke movement but lots of people found out they couldn't get them to start when they were cold unless they remove the air filter and sprayed a little gas or carb cleaner or something into the carb and then they started right up and ran perfectly.
So it certainly happens.
If the choke is closing all the way, then you start considering the level and the float bowl is too low due to leaking out or seeping or whatever.
If this happens after only several hours or just a day or two then it would have to be a leak. If it happens over a week plus the gas level could be evaporating in the bowl but that's not going to happen just overnight.
Someone mentioned the carb solenoid not having enough voltage during cranking to stay open but I can't see I've ever seen that and would be highly unlikely.
Those things don't take much current at all to stop open so if the electrical system is working properly that's probably not the issue.
HOWEVER, I have seen a couple of situations where the ignition switch was messed up or wired improperly and the carb solenoid had 12 volts when you click it the first notch to the on position but it did not have power at all when you were cranking.
It would be worth checking this on yours and would be a very quick easy test. You could just use a test light or voltmeter on The wire pigtail that goes to the solenoid and watch it come on when you click your key to the first on position and then make sure it stays on when you crank the engine and hold the switch in the crank position.
Strange things happen with old ignition switches especially when they've gotten wet or when the key has been pushed and pulled and jostled around by hitting things.
I've seen a flaky ignition switch kill multiple ignition coils because it somehow internally allowed voltage for just a split second to go to the terminal which connected the kill wire from the coil to the chassis when in the off position. Voltage to a coil there will kill it quickly if not instantly.
Having said that, I will say that the horizontally opposed twins can often be slow crankers but the coil system on these engines is pretty strong and even spitting one by hand will spark a spark plug so if it's turning over and spending the engine it probably has enough spark to run so I'm still guessing it's a fuel or enriching problem.
The answer to the fix is to find out why it's not getting enough fuel up into the throat of the carburetor when it cranks over.
This is why you start by checking the choke butterfly.
It's not common on these particular engines but these engines are also extremely old at this point and it would be rare for one this old to have not had throttle cable removed, replaced, carburetor off, etc or cable and levers and stuff just move around a little bit over the years so it's not pushing the choke butterfly closed far enough.
There was a whole rash of Kohler single courage engines a few years back coming from the factory with the chokes not adjusted to close far enough. Fix was as easy as using a torx driver on a purple paint marked screw to increase the choke movement but lots of people found out they couldn't get them to start when they were cold unless they remove the air filter and sprayed a little gas or carb cleaner or something into the carb and then they started right up and ran perfectly.
So it certainly happens.
If the choke is closing all the way, then you start considering the level and the float bowl is too low due to leaking out or seeping or whatever.
If this happens after only several hours or just a day or two then it would have to be a leak. If it happens over a week plus the gas level could be evaporating in the bowl but that's not going to happen just overnight.
Someone mentioned the carb solenoid not having enough voltage during cranking to stay open but I can't see I've ever seen that and would be highly unlikely.
Those things don't take much current at all to stop open so if the electrical system is working properly that's probably not the issue.
HOWEVER, I have seen a couple of situations where the ignition switch was messed up or wired improperly and the carb solenoid had 12 volts when you click it the first notch to the on position but it did not have power at all when you were cranking.
It would be worth checking this on yours and would be a very quick easy test. You could just use a test light or voltmeter on The wire pigtail that goes to the solenoid and watch it come on when you click your key to the first on position and then make sure it stays on when you crank the engine and hold the switch in the crank position.
Strange things happen with old ignition switches especially when they've gotten wet or when the key has been pushed and pulled and jostled around by hitting things.
I've seen a flaky ignition switch kill multiple ignition coils because it somehow internally allowed voltage for just a split second to go to the terminal which connected the kill wire from the coil to the chassis when in the off position. Voltage to a coil there will kill it quickly if not instantly.
#34
M
Machinist24
M
Machinist24
Maybe it's because I'm a machinist but I bought the push type primer bulbs and let the gas get low in the fuel tank. Then I drilled a hole in the tank at a low level and put a male outlet in the hole from the inside and put a nut on the outside with caulk added. I attached a fuel line to the outside and ran it to the carburetor where I drilled and tapped a hole between the choke and the cylinder and put the primer bulb in the line then attached it to the carburetor inlet I just installed. I give it a couple pumps before cranking and my engines all start easily.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#35
tgzzzz
tgzzzz
As I learned on this forum ... I adjusted the choke cable to fully close et voila!
#36
T
Tom O'
T
Tom O'
Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#37
S
skiman
S
skiman
ive had older twins not start so easy because of the reduced crankcase pressure due to age wear...still runs good but the osolating crankcase pressures dont work well enough to get the fuel pump to work correctly at low rpms...replacing with a low pressure...2.5 to 4 psi...low volume...80 liters per hour or 20 gallons per hour ...electric fuel pump worked every time...less than 20 bucks on ebay...
#38
Z
Zue
Z
Zue
Check to see if choke is working properlyBriggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#39
B
bk10s
B
bk10s
I really appreciate everyone's patience with this. Visually, it looks like the choke is closing. I adjusted the cable back, and it does seem to start easier. Not sure if the easier start was from the cable adjustment or because I started it about 4 hours ago. It is -15 wind chill here in WI! How far back can the cable be adjusted? I'm wondering if this has been adjusted in the past. The cable casing does not protrude beyond the adjuster. The electric fuel pump concept is interesting.
#40
B
bk10s
B
bk10s
What would I do besides making sure the valves are adjusted properly?Sounds like intake valve not closing tight.
#41
S
Ss4000
S
Ss4000
I would try a lighter weight oil if you have not already done so for this extreme cold weather. Also, just use a squirt of starting fluid if that is not a problem for your circumstance. Hope these ideas help.
#43
T
TobyU
They don't get tight on these. They get loose
T
TobyU
Nothing, because that's not going to be the problem. If you adjusted the valves even close when you did it.....What would I do besides making sure the valves are adjusted properly?
They don't get tight on these. They get loose
#44
T
TobyU
Since choke is most important for this situation, you have someone hold the handle control to full choke and then you loosen clamp and move cable outer part until choke is fully closed and tight.
Then tighten clamp.
Then move lever back and forth to make sure it's is still closing fully.
Sometimes you have to have lever like 1mm just a little bit not all the way to choke and do this same procedure so when you push lever all the way it is pushing choke even more toward full closed.
T
TobyU
It's not a matter of how far back out can be adjusted. Only rarely will you have one that won't work at buy choke and stop.I really appreciate everyone's patience with this. Visually, it looks like the choke is closing. I adjusted the cable back, and it does seem to start easier. Not sure if the easier start was from the cable adjustment or because I started it about 4 hours ago. It is -15 wind chill here in WI! How far back can the cable be adjusted? I'm wondering if this has been adjusted in the past. The cable casing does not protrude beyond the adjuster. The electric fuel pump concept is interesting.
Since choke is most important for this situation, you have someone hold the handle control to full choke and then you loosen clamp and move cable outer part until choke is fully closed and tight.
Then tighten clamp.
Then move lever back and forth to make sure it's is still closing fully.
Sometimes you have to have lever like 1mm just a little bit not all the way to choke and do this same procedure so when you push lever all the way it is pushing choke even more toward full closed.
#45
B
batrater
B
batrater
This is good info, I have the exact same problem with my 16 hp v-twin cub cadet, (I know the choke works great) I keep a spray bottle with gasoline handy, a quick spray directly into the carburator fires it up on first crank, sounds like I have a vacuum problem from what I'm reading
#46
T
TobyU
You need to get in there and make absolutely certain the choke is shutting all the way because on those newer v twins it's usually a little rod you can reach down with your finger and move up and down. You will often find that when the choke is fully on you can reach down and push the lever rod a little further up which is closing the choke fully. Try that next time.
If you're starting the mower within 5 to 10 days of the last time you started it the vacuum shouldn't even be an issue.
The bowl of the carburetor should still be almost full and most the time it's still completely full because any amount that is evaporated the float has allowed more to come in and there's still more in the fuel line to trickle in as you don't really need gravity pressure or the pump from the fuel pump to let a little bit more like that flow in.
The only time the vacuum comes into play is if the bowl has gotten below let's say half full or even empty because of a slight seepage or leak. In this case the engine has to continue to crank and provide proper vacuum to the pulsator pump until it can fill the bowl back up before it will be able to suck the fuel up the venturi tube and into the intake.
It's also possible, of course a lot of things are possible that aren't supposed to be, that the needle valve in the carb is not actually shutting off properly which is a common problem on older engines.
This allows the throat of the carburetor to puddle or pull up with gas.
On a gravity tank without a fuel pump it will continue to flood and leak and smell up your garage etc and be very hard to start and require no choke to start and then smoke some white puff of smoke when you first fire it up BUT on a fuel pump motor if the tank isn't very full they won't really be any pressure or way for gas to continue to flow into the bowl so it will only half what kind of in the three or four inches of fuel line before the carburetor and it can flood out the carb and kind of act like a siphoning action and then that can evaporate because there's no more fuel to come after it to keep flooding out. So the bowl can be lower than it needs to be or should be when you try to start it next time.
This isn't really common but as I said it is possible.
There's several different types of air filter setups on those and some are easier to do this than others but if you can take the air filter off and put the flat of your hand on the plastic inlet area there to block it off completely and put your throttle to fast or choke, doesn't matter and crank it up and see if it starts quicker this way you will also know that it's probably a choke issue.
T
TobyU
Not necessarily but you should look into it. The only thing you know for certain is it's not getting enough fuel into the intake when you start it unless you spray the gas in there yourself.This is good info, I have the exact same problem with my 16 hp v-twin cub cadet, (I know the choke works great) I keep a spray bottle with gasoline handy, a quick spray directly into the carburator fires it up on first crank, sounds like I have a vacuum problem from what I'm reading
You need to get in there and make absolutely certain the choke is shutting all the way because on those newer v twins it's usually a little rod you can reach down with your finger and move up and down. You will often find that when the choke is fully on you can reach down and push the lever rod a little further up which is closing the choke fully. Try that next time.
If you're starting the mower within 5 to 10 days of the last time you started it the vacuum shouldn't even be an issue.
The bowl of the carburetor should still be almost full and most the time it's still completely full because any amount that is evaporated the float has allowed more to come in and there's still more in the fuel line to trickle in as you don't really need gravity pressure or the pump from the fuel pump to let a little bit more like that flow in.
The only time the vacuum comes into play is if the bowl has gotten below let's say half full or even empty because of a slight seepage or leak. In this case the engine has to continue to crank and provide proper vacuum to the pulsator pump until it can fill the bowl back up before it will be able to suck the fuel up the venturi tube and into the intake.
It's also possible, of course a lot of things are possible that aren't supposed to be, that the needle valve in the carb is not actually shutting off properly which is a common problem on older engines.
This allows the throat of the carburetor to puddle or pull up with gas.
On a gravity tank without a fuel pump it will continue to flood and leak and smell up your garage etc and be very hard to start and require no choke to start and then smoke some white puff of smoke when you first fire it up BUT on a fuel pump motor if the tank isn't very full they won't really be any pressure or way for gas to continue to flow into the bowl so it will only half what kind of in the three or four inches of fuel line before the carburetor and it can flood out the carb and kind of act like a siphoning action and then that can evaporate because there's no more fuel to come after it to keep flooding out. So the bowl can be lower than it needs to be or should be when you try to start it next time.
This isn't really common but as I said it is possible.
There's several different types of air filter setups on those and some are easier to do this than others but if you can take the air filter off and put the flat of your hand on the plastic inlet area there to block it off completely and put your throttle to fast or choke, doesn't matter and crank it up and see if it starts quicker this way you will also know that it's probably a choke issue.
#47
N
nthnwdhs
Here is the video:
and at about 3:12 it shows the 4 circuits. Maybe you just need to clean the carbi?
N
nthnwdhs
Not sure if you've tried this, dismissed it or even if it applies to a BS carbi but I watched this video a while ago on how a carburetor works - it explains the four circuits of a carbi. What you've described here sounds like the starter circuit in the carbi not working but the main circuit working fine.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
Here is the video:
#49
T
TobyU
Technically you could break down the circuits into four circuits of a carb like that but people really don't.
Sometimes for clarification or educational purposes I will tell customers that there's two basic circuits on a carb and I don't mean the ones they're talking about. I mean the air and the fuel because people think sometimes that a dirty air filter or dirty Dusty conditions causes the mower not to start and run after stuff gets in the carburetor and clogs up the jets.
I explained to them that that's not the case and all the clogging internal carburetor passages has to come from what's in the gas tank or from the fuel itself congealing etc or water grease bubbles what have you.
The fuel and air never actually mix at least not until the very very end and only when the engine is running. No matter how much dirt and dust you operate the lawn mower in even if you do it without an air filter, which is bad on the engine especially the rings and cylinder walls etc even though people have gotten by with it for years, you're not going to get dirt into the carburetor bowl and clog up the jets.
But as far as what this video is relating to most people just refer to the running circuit and us old text or younger ones with lots of experience especially with older equipment will refer to the primary and secondary circuits or Jets or the high speed and low speed.
It's a little clearer when you start looking at the two cycle or similar engines with the very small carbs with two separate mixture screws.
One literally controls the gas flow at larger throttle openings and the other one controls the mixture at almost closed throttle idle.
In the old days pretty much all equipment had two mixture screws along with your minimum idle speed. Lots of people confuse idle stop screws for mixture screws.
You had the large one you could operate with your thumb on the bottom of the bowl that screwed the needle up and down and adjusted how much fuel could get sucked through the carburetor from the Venturi effect of the air going down the throat with it running then you had the smaller one up higher on the carb that controlled your idle mixture when the engine was running at idle and much slower speeds.
What they're going to call the choke or starting circuit most people just refer to as a choke or whatever it doesn't really deserve being called its own separate circuit.
Again, in the old days you had a choke that was a butterfly that closed just like putting your hand over the throat of the carb. Then they went to a primer bulb which squirts gas right into the carburetor actually by blowing air into the bowl which displaces the gas up the metering rod tube emulsion tube whatever you want to call it into the throat of the carburetor the exact same way it gets sucked up through his little straw like hole when the air is rushing over it.
There's other ways to do it but that's the two main ways.
Motorcycles have typically used a different approach and some of the small newer handheld blowers and trimmers , especially the last of the two cycle ones used a similar approach to the motorcycles as in an enriching situation which they would call a enriching or riching circuit but like I said most of us don't bother to consider that really its own separate thing.
Most the time you're dealing with a choke and it's not like it can get clogged up or anything. The flat / butterfly either closes all the way or it doesn't.
It is worth noting there has been a couple of tsbs and revisions over the years mainly on Briggs & Stratton but it's probably happened elsewhere where they made the butterfly with not complete coverage of the whole and they left a cutout in the corner. Often on equipment they would be holes drilled in the butterfly too so they could have just enough sealing without flooding it. Some of these I think it was the overhead valve vertical crankshaft ready start Briggs had an improved replacement butterfly that you would replace to make them start better.
It's been a few years now since I've had the situation and it could have actually been on a hot restart issue where it was two complete and the new one had the corner cut out because I think I remember modifying one to like the new style and cutting it out myself instead of having to buy one.
Regardless, pretty much we deal with the high-speed running circuit and the low speed idle circuit which on many things isn't even a concern today because for the vast majority of lawn mowers that are standard 21 and 22 walk behind and push mowers, there is no throttle speed so you're never really going to know if it runs well at idle or not unlike a rider or many of the snow blowers.
The trick is knowing that many of these carburetor designs will not run smoothly and even surge extremely like the Chinese Huayi carburetor.
It's common procedure for those of us who actually keep the original carburetors and clean them which is a very good day because most shops and most people throw away a perfectly good carburetor and often replace it with an inferior quality no name carburetor because the factory one is quite good. It doesn't go bad, it just gets clogged up.
The main jet for the primary high speed running circuit is the one that gets it to run but if the secondary or idle circuit is still restricted or clogged it will surge up and down and it will not run at idle..
The old tecumseh's were similar but not as extreme. When they ran but surged about 15 or 20% you could pretty much guarantee you needed to take out the secondary idol circuit jet and run a wire through it and blow it out well with car cleaner and compressed air. Then they would almost always smooth out to 100%.
These are the tricky circuits that you have to worry about and that's probably why that's almost of us are concerned with. The choke is fully mechanical and easy to inspect and observe correct operation or not.
Air is also obvious as I do get a number of mowers in every year that will not start and run or run properly and the only reason is the air filter is so clogged up they cannot breathe..
T
TobyU
I'm assuming all of that's true without actually watching the video but it's from one of those engineers standpoints.Not sure if you've tried this, dismissed it or even if it applies to a BS carbi but I watched this video a while ago on how a carburetor works - it explains the four circuits of a carbi. What you've described here sounds like the starter circuit in the carbi not working but the main circuit working fine.
Here is the video:and at about 3:12 it shows the 4 circuits. Maybe you just need to clean the carbi?
Technically you could break down the circuits into four circuits of a carb like that but people really don't.
Sometimes for clarification or educational purposes I will tell customers that there's two basic circuits on a carb and I don't mean the ones they're talking about. I mean the air and the fuel because people think sometimes that a dirty air filter or dirty Dusty conditions causes the mower not to start and run after stuff gets in the carburetor and clogs up the jets.
I explained to them that that's not the case and all the clogging internal carburetor passages has to come from what's in the gas tank or from the fuel itself congealing etc or water grease bubbles what have you.
The fuel and air never actually mix at least not until the very very end and only when the engine is running. No matter how much dirt and dust you operate the lawn mower in even if you do it without an air filter, which is bad on the engine especially the rings and cylinder walls etc even though people have gotten by with it for years, you're not going to get dirt into the carburetor bowl and clog up the jets.
But as far as what this video is relating to most people just refer to the running circuit and us old text or younger ones with lots of experience especially with older equipment will refer to the primary and secondary circuits or Jets or the high speed and low speed.
It's a little clearer when you start looking at the two cycle or similar engines with the very small carbs with two separate mixture screws.
One literally controls the gas flow at larger throttle openings and the other one controls the mixture at almost closed throttle idle.
In the old days pretty much all equipment had two mixture screws along with your minimum idle speed. Lots of people confuse idle stop screws for mixture screws.
You had the large one you could operate with your thumb on the bottom of the bowl that screwed the needle up and down and adjusted how much fuel could get sucked through the carburetor from the Venturi effect of the air going down the throat with it running then you had the smaller one up higher on the carb that controlled your idle mixture when the engine was running at idle and much slower speeds.
What they're going to call the choke or starting circuit most people just refer to as a choke or whatever it doesn't really deserve being called its own separate circuit.
Again, in the old days you had a choke that was a butterfly that closed just like putting your hand over the throat of the carb. Then they went to a primer bulb which squirts gas right into the carburetor actually by blowing air into the bowl which displaces the gas up the metering rod tube emulsion tube whatever you want to call it into the throat of the carburetor the exact same way it gets sucked up through his little straw like hole when the air is rushing over it.
There's other ways to do it but that's the two main ways.
Motorcycles have typically used a different approach and some of the small newer handheld blowers and trimmers , especially the last of the two cycle ones used a similar approach to the motorcycles as in an enriching situation which they would call a enriching or riching circuit but like I said most of us don't bother to consider that really its own separate thing.
Most the time you're dealing with a choke and it's not like it can get clogged up or anything. The flat / butterfly either closes all the way or it doesn't.
It is worth noting there has been a couple of tsbs and revisions over the years mainly on Briggs & Stratton but it's probably happened elsewhere where they made the butterfly with not complete coverage of the whole and they left a cutout in the corner. Often on equipment they would be holes drilled in the butterfly too so they could have just enough sealing without flooding it. Some of these I think it was the overhead valve vertical crankshaft ready start Briggs had an improved replacement butterfly that you would replace to make them start better.
It's been a few years now since I've had the situation and it could have actually been on a hot restart issue where it was two complete and the new one had the corner cut out because I think I remember modifying one to like the new style and cutting it out myself instead of having to buy one.
Regardless, pretty much we deal with the high-speed running circuit and the low speed idle circuit which on many things isn't even a concern today because for the vast majority of lawn mowers that are standard 21 and 22 walk behind and push mowers, there is no throttle speed so you're never really going to know if it runs well at idle or not unlike a rider or many of the snow blowers.
The trick is knowing that many of these carburetor designs will not run smoothly and even surge extremely like the Chinese Huayi carburetor.
It's common procedure for those of us who actually keep the original carburetors and clean them which is a very good day because most shops and most people throw away a perfectly good carburetor and often replace it with an inferior quality no name carburetor because the factory one is quite good. It doesn't go bad, it just gets clogged up.
The main jet for the primary high speed running circuit is the one that gets it to run but if the secondary or idle circuit is still restricted or clogged it will surge up and down and it will not run at idle..
The old tecumseh's were similar but not as extreme. When they ran but surged about 15 or 20% you could pretty much guarantee you needed to take out the secondary idol circuit jet and run a wire through it and blow it out well with car cleaner and compressed air. Then they would almost always smooth out to 100%.
These are the tricky circuits that you have to worry about and that's probably why that's almost of us are concerned with. The choke is fully mechanical and easy to inspect and observe correct operation or not.
Air is also obvious as I do get a number of mowers in every year that will not start and run or run properly and the only reason is the air filter is so clogged up they cannot breathe..
#50
N
NeilH
N
NeilH
Hello B. I have read the thread of your difficulties and suggestions. I'm not a mechanic but am old enough to have had experience. It reads to me as fuel supply trouble. Pardon me for asking simple questions. Do you have that inline fuel filter installed correctly? If not, it may have a check valve that is preventing fuel flow in the right direction. If you have spark while you turn the engine over with the spark plug(s) out, try spraying in some gas into the cylinder(s), replace the plug (even finger tight for now) and see if the engine fires. If it fires right away, then you likely confirmed that fuel supply is the issue. I recently had a grain auger engine that needed choke to run and then eventually would die. In checking the fuel system and taking off the fuel tank to check for debris, I found that the shut-off valve at the bottom of the fuel tank had vibrated to almost be closed. That had been an undiscovered problem for a few times in using that engine.
Regarding spark, your posts sound like you would know this, but check for spark and spark quality. Spark should be good because you replaced the spark plugs and coils. Your engine may not have a set of points but, if it does, check the points. Timing being off can be a problem also. I have a Tecumseh mower engine that has a key in the flywheel that, over time and use, becomes bent enough that the engine won't start or run well so I have needed to replace that key.
Regarding spark, your posts sound like you would know this, but check for spark and spark quality. Spark should be good because you replaced the spark plugs and coils. Your engine may not have a set of points but, if it does, check the points. Timing being off can be a problem also. I have a Tecumseh mower engine that has a key in the flywheel that, over time and use, becomes bent enough that the engine won't start or run well so I have needed to replace that key.
#51
B
bk10s
B
bk10s
I'm sorry I have been away and not reported back. Got involved with a water pump and a failed rear differential on my truck! It's a journey......
I will try to get a better look at the choke an if it is closing completely. Tried to start yesterday and took forever. Popped several times while cranking. The carb is in the front and difficult to access without taking off the hood. Further complicated by the snowblower on the front!
I will try to get a better look at the choke an if it is closing completely. Tried to start yesterday and took forever. Popped several times while cranking. The carb is in the front and difficult to access without taking off the hood. Further complicated by the snowblower on the front!
#52
goodO1boydws
I fought with one for a few years before I bit the bullet and went looking again.
The last time it had been something like $100.00, this time it was abut $25.00
goodO1boydws
If you've hit your frustration level, the carb is cheap now that they're all coming from China.I'm sorry I have been away and not reported back. Got involved with a water pump and a failed rear differential on my truck! It's a journey......
I will try to get a better look at the choke an if it is closing completely. Tried to start yesterday and took forever. Popped several times while cranking. The carb is in the front and difficult to access without taking off the hood. Further complicated by the snowblower on the front!
I fought with one for a few years before I bit the bullet and went looking again.
The last time it had been something like $100.00, this time it was abut $25.00
#53
T
TobyU
Even use ones we're going for almost $100 because the cheapest new one was about 138 on Amazon.
Then all of a sudden they have some aftermarket ones pop up when some Chinese company finally copied them for $36 to your door.
The only reason I bought one or was looking for one is because a man brought me a lawn mower that he had had worked on in Florida before he moved North and when they gave it back to him it had no carburetor installed on it.
They had stuck the bolts back through the air filter housing and screwed them into the engine but no carb.
That was a shame because if he would have brought me the original carb he would have saved $36.
My main point here is 99.9% of the time you do not need a new carburetor.
I get calls way too often from people who say they cleaned out the carburetor but it still won't run right and I just roll my eyes and shake my head and wish they hadn't because there is a decent amount of likelihood that they've now messed something else up I will have to fix or fix some leak they've created because they messed with it and they obviously don't know what they're doing or it would be running properly and they wouldn't be needing to call me.
Almost always, if you understand how the carbs work and know what you're doing with each particular model or at least design style, you can clean them out properly and get them running perfectly without needing to buy a new one.
It is possible to run into something that's so rusted up that you can't even get it apart without it breaking and also possible to come into one that someone has tried to work on before and screwed up a passage or the jet and made the holes too big and that's not going to be fixed without some at least used replacement parts.
Far too often now, especially on YouTube because every video I see is either done the hard way or the wrong way.... people no a little bit or at least enough to be dangerous or maybe enough to get by most of the time maybe 50% to 60% of the time BUT they don't really understand it.
These people do what they call cleaning out a carburetor and never even get to the actual Jack cuz they don't know where it's at and then others take the whole thing off the machine which is a complete waste of time and put it in their fancy newfangled ultrasonic cleaner with whatever cleaner or their concoction of what is it now they're using half simple Green and half vinegar or something else. I don't even remember because it's a waste of time and product.
That's just throwing it in there and hoping it can do the job of cleaning out all the passages without really knowing where they are and doing it yourself.
A Honda carb or one of the Huayi ones are probably the best ones to start with so a person can actually learn how the carb is made and how the holes and jets and pastures all interact but you don't have to know all that if somebody just shows you one time how to take it apart and clean it all out.
Note that this is almost never necessary on a Huayi and only necessary occasionally on a Honda because you can do everything you need to do with it still not on the machine by only removing the float bowl and then unscrewing the main jet and on the Huayi even if you have to clean out the secondary jet and passages you can do this with it still on the machine.
You can also do this on a Honda on the machine however since you have to remove the air filter housing to do it you might as well just pop the fuel line off and slide it off, tilt it over to pop the linkage off of it and then hold it in your hand to do it or place it on the bench.
I don't do it first though because many times when it Honda doesn't start at all then it just needs the main jet cleaned out and it will run perfectly once you do that. However about 30 or 40% of the time you will have one that surges afterwards or if you get one that comes in that already surges once the choke opens up then you're going to have to clean out the secondary idle jet anyways so you might as well just take it off.
There's a big difference from working on your own stuff peddling on the weekend when you have three or four hours to kill with nothing to do so you're going to spend 45 minutes or an hour messing with you more versus having a hundred of them lined up with seemingly no end in sight when you are trying to fix them as quickly and efficiently as possible so you can get on to the next one. Time is of the essence because for some reason people are obsessed with cutting their grass and they are extremely unresourceful in finding ways to do this when their mower is in the shop.
T
TobyU
This does happen. Just three or four years ago you couldn't find any Kawasaki replacement carbs on eBay or Amazon for the self-propelled mowers like John Deere 14 SB etc.If you've hit your frustration level, the carb is cheap now that they're all coming from China.
I fought with one for a few years before I bit the bullet and went looking again.
The last time it had been something like $100.00, this time it was abut $25.00
Even use ones we're going for almost $100 because the cheapest new one was about 138 on Amazon.
Then all of a sudden they have some aftermarket ones pop up when some Chinese company finally copied them for $36 to your door.
The only reason I bought one or was looking for one is because a man brought me a lawn mower that he had had worked on in Florida before he moved North and when they gave it back to him it had no carburetor installed on it.
They had stuck the bolts back through the air filter housing and screwed them into the engine but no carb.
That was a shame because if he would have brought me the original carb he would have saved $36.
My main point here is 99.9% of the time you do not need a new carburetor.
I get calls way too often from people who say they cleaned out the carburetor but it still won't run right and I just roll my eyes and shake my head and wish they hadn't because there is a decent amount of likelihood that they've now messed something else up I will have to fix or fix some leak they've created because they messed with it and they obviously don't know what they're doing or it would be running properly and they wouldn't be needing to call me.
Almost always, if you understand how the carbs work and know what you're doing with each particular model or at least design style, you can clean them out properly and get them running perfectly without needing to buy a new one.
It is possible to run into something that's so rusted up that you can't even get it apart without it breaking and also possible to come into one that someone has tried to work on before and screwed up a passage or the jet and made the holes too big and that's not going to be fixed without some at least used replacement parts.
Far too often now, especially on YouTube because every video I see is either done the hard way or the wrong way.... people no a little bit or at least enough to be dangerous or maybe enough to get by most of the time maybe 50% to 60% of the time BUT they don't really understand it.
These people do what they call cleaning out a carburetor and never even get to the actual Jack cuz they don't know where it's at and then others take the whole thing off the machine which is a complete waste of time and put it in their fancy newfangled ultrasonic cleaner with whatever cleaner or their concoction of what is it now they're using half simple Green and half vinegar or something else. I don't even remember because it's a waste of time and product.
That's just throwing it in there and hoping it can do the job of cleaning out all the passages without really knowing where they are and doing it yourself.
A Honda carb or one of the Huayi ones are probably the best ones to start with so a person can actually learn how the carb is made and how the holes and jets and pastures all interact but you don't have to know all that if somebody just shows you one time how to take it apart and clean it all out.
Note that this is almost never necessary on a Huayi and only necessary occasionally on a Honda because you can do everything you need to do with it still not on the machine by only removing the float bowl and then unscrewing the main jet and on the Huayi even if you have to clean out the secondary jet and passages you can do this with it still on the machine.
You can also do this on a Honda on the machine however since you have to remove the air filter housing to do it you might as well just pop the fuel line off and slide it off, tilt it over to pop the linkage off of it and then hold it in your hand to do it or place it on the bench.
I don't do it first though because many times when it Honda doesn't start at all then it just needs the main jet cleaned out and it will run perfectly once you do that. However about 30 or 40% of the time you will have one that surges afterwards or if you get one that comes in that already surges once the choke opens up then you're going to have to clean out the secondary idle jet anyways so you might as well just take it off.
There's a big difference from working on your own stuff peddling on the weekend when you have three or four hours to kill with nothing to do so you're going to spend 45 minutes or an hour messing with you more versus having a hundred of them lined up with seemingly no end in sight when you are trying to fix them as quickly and efficiently as possible so you can get on to the next one. Time is of the essence because for some reason people are obsessed with cutting their grass and they are extremely unresourceful in finding ways to do this when their mower is in the shop.
#54
goodO1boydws
goodO1boydws
First of all, these engines are about as simple as you're liable to run into today.
It appears that the plugs are either new and/or have been cleaned and gapped properly, and that the fuel filter and air filter and prefilter (if it has one) have been checked and replaced if necessary.
Issues with engine timing, and "emission controls" are so rare as to be not of consideration.
If the engine struggles to start but then runs ok once started there are only a couple things that it CAN be.
If it appears to run properly once started, the valves-(even if sightly misadjusted), are set closely enough.
Again, if it appears to run properly once started and has reasonable power, the compression-(even if one cylinder is lower than the other, or both-are a little low) is close enough.
If it starts AT ALL, the ignition is working ok-AND if it runs ok after starting, the odds of it being an ACTUAL ignition issue are effectively zero. (If its cranking too slowly to generate a consistent spark while attempting to start that is something else entirely.).
So that leaves the fuel system.
Since it DOES start, and it then apparently DOES runs ok-with reasonable power once started, it is getting AT LEAST enough fuel.
In fact, it is likely to be getting TOO MUCH fuel while attempting to start-as evidenced by the "popping".
If someone doesn't have the skills, tools, time, or inclination to clean and set a carburetor up properly, it makes sense to either take it to someone who does-OR (if determined to "solve" the problem themselves), to start with a clean slate.
In this case, since other reasonably likely possibilities have effectively been eliminated from the equation, that means trying a DIFFERENT KNOWN TO BE GOOD OR NEW carburetor-one that HAS NOT been tinkered-with.
The old one is (by now) likely to either be in need of a proper cleaning, is misadjusted, or has worn parts.
The latter includes, (but is not limited to) a float level that is too high from a float bouncing so many times it is no longer in the proper position, OR a worn needle/seat combination that allows too much gas to be sneaking into the carburetor (in SPITE of a float that may still be set properly), OR a worn throttle shaft and/or a worn throttle shaft BORE in the carburetor's casting (either of which can allow enough UNMETERED AND UNMETERABLE air OR fuel OR BOTH to sneak past the throttle plate WHEN ATTEMPTING TO START, (by distorting the fuel to air mixture from what it would be if such excess clearance was not present).
Any single one of these conditions can easily make an engine difficult to start-and in combination even more difficult.
It appears that the plugs are either new and/or have been cleaned and gapped properly, and that the fuel filter and air filter and prefilter (if it has one) have been checked and replaced if necessary.
Issues with engine timing, and "emission controls" are so rare as to be not of consideration.
If the engine struggles to start but then runs ok once started there are only a couple things that it CAN be.
If it appears to run properly once started, the valves-(even if sightly misadjusted), are set closely enough.
Again, if it appears to run properly once started and has reasonable power, the compression-(even if one cylinder is lower than the other, or both-are a little low) is close enough.
If it starts AT ALL, the ignition is working ok-AND if it runs ok after starting, the odds of it being an ACTUAL ignition issue are effectively zero. (If its cranking too slowly to generate a consistent spark while attempting to start that is something else entirely.).
So that leaves the fuel system.
Since it DOES start, and it then apparently DOES runs ok-with reasonable power once started, it is getting AT LEAST enough fuel.
In fact, it is likely to be getting TOO MUCH fuel while attempting to start-as evidenced by the "popping".
If someone doesn't have the skills, tools, time, or inclination to clean and set a carburetor up properly, it makes sense to either take it to someone who does-OR (if determined to "solve" the problem themselves), to start with a clean slate.
In this case, since other reasonably likely possibilities have effectively been eliminated from the equation, that means trying a DIFFERENT KNOWN TO BE GOOD OR NEW carburetor-one that HAS NOT been tinkered-with.
The old one is (by now) likely to either be in need of a proper cleaning, is misadjusted, or has worn parts.
The latter includes, (but is not limited to) a float level that is too high from a float bouncing so many times it is no longer in the proper position, OR a worn needle/seat combination that allows too much gas to be sneaking into the carburetor (in SPITE of a float that may still be set properly), OR a worn throttle shaft and/or a worn throttle shaft BORE in the carburetor's casting (either of which can allow enough UNMETERED AND UNMETERABLE air OR fuel OR BOTH to sneak past the throttle plate WHEN ATTEMPTING TO START, (by distorting the fuel to air mixture from what it would be if such excess clearance was not present).
Any single one of these conditions can easily make an engine difficult to start-and in combination even more difficult.
#55
T
TobyU
It is, however, possible that there is another minor air leak somewhere between carb and intake or intake and engine or even the throttle shaft that could be letting air in thus reducing the effectiveness of the choke but it's fairly unlikely.
We often get into the mentality of saying this or that can't happen when in reality if you do this long enough you'll see a decent number of things happen right in front of you that aren't supposed to be able to happen or "never" happen.
You're right about the troubleshooting though as far too often people don't largely think these things out or just don't understand how the systems work and they replace parts hoping and grasping but in the end they're just wasting time and money.
I'm not in real agreement about the carburetor though because half the time when people buy these eBay and Amazon carburetors it's not really a fact that it's a known good carburetor. New doesn't always mean good.
Also, pretty much 99% of these if not 100% of these engines unless you happen to have something old enough to have a Tecumseh on it and those weren't common on these machines....does not have any float adjustment whatsoever because there is no bendable tang like the Tecumseh had on both the brass and the plastic version of the float.
Everything breaks from the overhead valve engines and even the flat l heads on the riders for a number of years before that and all of the new Chinese built engines etc have a plastic float but no adjustment of the float height and none of that ever gets out of spec.
The needle and seat leakage that you speak of can occur and often does on older machines and can occur as early as 8 years or anytime if a speck of dirt or hair gets in there but that almost never results in an engine that won't start or run properly..
At worst it could flood out or get a plug wet or even hydralocky cylinder but after removing the plug and cranking it over a few times, it will start right back up and run fine. The problem with the leaky needle and seat almost always occurs and presents itself as flooding after it sits and not needing any choke to start and fuel migrating over into the crankcase and diluting the oil and the gas tank being much lower than it was when you parked it or even empty.
Once one is found to be doing this then it certainly should be fixed because the workaround of the fuel shut off never works long-term because you eventually forget to turn it off and you flood things out again.
I just don't believe in replacing parts. I only do so when I absolutely have to.
I would rather keep an old original carburetor on a Briggs single OHV and put a new needle and seat into it than to put a brand new carburetor on it whether it be a Briggs & Stratton way over price carburetor or a generic cheapy readily available online.
They sing so rarely give any odd running conditions as long as you clean them out well so the only time I would ever even consider another one would be if I had some very weird running issue I couldn't put a finger on and then I would swap one from another perfectly good running engine so I did know absolutely for sure that that carburetor was perfect.
I've done this twice in the past 15 years.
Once was on a Briggs overhead valve single like we're talking about on a used mower I purchased that would start and run perfectly at idle but would not rev up.
Now it's been over a decade so I don't remember exactly how it acted I don't think it popped or spit or anything like that but it seemed more to lean out of fuel but again I don't remember exactly.
It must have acted like a lean condition because I would have probably sprayed some gas into the throat while revving it up to see if I could improve the situation but I did swap a carburetor onto it just to make sure and it ran exactly the same so that ruled out carb and fuel.
I also remember checking the valve adjustment and such but I didn't bother to do any more digging. It's possible the engine had been apart and the camshaft was installed a notch or two off or something like that.
Like with my other post, it was far quicker to just throw one of my perfectly good running engines on that machine which is what I did and it was ready for sale that day and sold it in the next 3 days. It wasn't worth taking the time to disassemble that engine and put new parts into it when I had funny of good used donor engines.
I was so busy after that I don't think I ever even tore that engine apart to look inside of it. Now, I don't toss anything until I scavenge all the parts I can off of and out of them..
I did this once again on one of the newer Briggs small push mower overhead valve engines the first year those were out.
Had that one that was surging badly. A number of them do that from time to time but this was quite extreme and I had already cleaned out the carburetor. So I decided to swap another carb that ran perfectly onto it and did the exact same thing so obviously it wasn't the carb.
I was able to increase the speed on that one which is a little low and it smooth out to acceptable levels but still not as good as I would have liked. Really never did figure out exactly what was wrong with that one but that was in the first round of them I ever saw. Haven't ran into the situation again.
I do like to understand how these things work and I love to troubleshoot more than I actually like to fix.
T
TobyU
Very true but it seems in this case he just isn't getting enough fuel because it was stated before that he sprays some gas or starting fluid etc into the carb it fires right up, if I am remembering the earlier post correctly.First of all, these engines are about as simple as you're liable to run into today.
It appears that the plugs are either new and/or have been cleaned and gapped properly, and that the fuel filter and air filter and prefilter (if it has one) have been checked and replaced if necessary.
Issues with engine timing, and "emission controls" are so rare as to be not of consideration.
If the engine struggles to start but then runs ok once started there are only a couple things that it CAN be.
If it appears to run properly once started, the valves-(even if sightly misadjusted), are set closely enough.
Again, if it appears to run properly once started and has reasonable power, the compression-(even if one cylinder is lower than the other, or both-are a little low) is close enough.
If it starts AT ALL, the ignition is working ok-AND if it runs ok after starting, the odds of it being an ACTUAL ignition issue are effectively zero. (If its cranking too slowly to generate a consistent spark while attempting to start that is something else entirely.).
So that leaves the fuel system.
Since it DOES start, and it then apparently DOES runs ok-with reasonable power once started, it is getting AT LEAST enough fuel.
In fact, it is likely to be getting TOO MUCH fuel while attempting to start-as evidenced by the "popping".
If someone doesn't have the skills, tools, time, or inclination to clean and set a carburetor up properly, it makes sense to either take it to someone who does-OR (if determined to "solve" the problem themselves), to start with a clean slate.
In this case, since other reasonably likely possibilities have effectively been eliminated from the equation, that means trying a DIFFERENT KNOWN TO BE GOOD OR NEW carburetor-one that HAS NOT been tinkered-with.
The old one is (by now) likely to either be in need of a proper cleaning, is misadjusted, or has worn parts.
The latter includes, (but is not limited to) a float level that is too high from a float bouncing so many times it is no longer in the proper position, OR a worn needle/seat combination that allows too much gas to be sneaking into the carburetor (in SPITE of a float that may still be set properly), OR a worn throttle shaft and/or a worn throttle shaft BORE in the carburetor's casting (either of which can allow enough UNMETERED AND UNMETERABLE air OR fuel OR BOTH to sneak past the throttle plate WHEN ATTEMPTING TO START, (by distorting the fuel to air mixture from what it would be if such excess clearance was not present).
Any single one of these conditions can easily make an engine difficult to start-and in combination even more difficult.
It is, however, possible that there is another minor air leak somewhere between carb and intake or intake and engine or even the throttle shaft that could be letting air in thus reducing the effectiveness of the choke but it's fairly unlikely.
We often get into the mentality of saying this or that can't happen when in reality if you do this long enough you'll see a decent number of things happen right in front of you that aren't supposed to be able to happen or "never" happen.
You're right about the troubleshooting though as far too often people don't largely think these things out or just don't understand how the systems work and they replace parts hoping and grasping but in the end they're just wasting time and money.
I'm not in real agreement about the carburetor though because half the time when people buy these eBay and Amazon carburetors it's not really a fact that it's a known good carburetor. New doesn't always mean good.
Also, pretty much 99% of these if not 100% of these engines unless you happen to have something old enough to have a Tecumseh on it and those weren't common on these machines....does not have any float adjustment whatsoever because there is no bendable tang like the Tecumseh had on both the brass and the plastic version of the float.
Everything breaks from the overhead valve engines and even the flat l heads on the riders for a number of years before that and all of the new Chinese built engines etc have a plastic float but no adjustment of the float height and none of that ever gets out of spec.
The needle and seat leakage that you speak of can occur and often does on older machines and can occur as early as 8 years or anytime if a speck of dirt or hair gets in there but that almost never results in an engine that won't start or run properly..
At worst it could flood out or get a plug wet or even hydralocky cylinder but after removing the plug and cranking it over a few times, it will start right back up and run fine. The problem with the leaky needle and seat almost always occurs and presents itself as flooding after it sits and not needing any choke to start and fuel migrating over into the crankcase and diluting the oil and the gas tank being much lower than it was when you parked it or even empty.
Once one is found to be doing this then it certainly should be fixed because the workaround of the fuel shut off never works long-term because you eventually forget to turn it off and you flood things out again.
I just don't believe in replacing parts. I only do so when I absolutely have to.
I would rather keep an old original carburetor on a Briggs single OHV and put a new needle and seat into it than to put a brand new carburetor on it whether it be a Briggs & Stratton way over price carburetor or a generic cheapy readily available online.
They sing so rarely give any odd running conditions as long as you clean them out well so the only time I would ever even consider another one would be if I had some very weird running issue I couldn't put a finger on and then I would swap one from another perfectly good running engine so I did know absolutely for sure that that carburetor was perfect.
I've done this twice in the past 15 years.
Once was on a Briggs overhead valve single like we're talking about on a used mower I purchased that would start and run perfectly at idle but would not rev up.
Now it's been over a decade so I don't remember exactly how it acted I don't think it popped or spit or anything like that but it seemed more to lean out of fuel but again I don't remember exactly.
It must have acted like a lean condition because I would have probably sprayed some gas into the throat while revving it up to see if I could improve the situation but I did swap a carburetor onto it just to make sure and it ran exactly the same so that ruled out carb and fuel.
I also remember checking the valve adjustment and such but I didn't bother to do any more digging. It's possible the engine had been apart and the camshaft was installed a notch or two off or something like that.
Like with my other post, it was far quicker to just throw one of my perfectly good running engines on that machine which is what I did and it was ready for sale that day and sold it in the next 3 days. It wasn't worth taking the time to disassemble that engine and put new parts into it when I had funny of good used donor engines.
I was so busy after that I don't think I ever even tore that engine apart to look inside of it. Now, I don't toss anything until I scavenge all the parts I can off of and out of them..
I did this once again on one of the newer Briggs small push mower overhead valve engines the first year those were out.
Had that one that was surging badly. A number of them do that from time to time but this was quite extreme and I had already cleaned out the carburetor. So I decided to swap another carb that ran perfectly onto it and did the exact same thing so obviously it wasn't the carb.
I was able to increase the speed on that one which is a little low and it smooth out to acceptable levels but still not as good as I would have liked. Really never did figure out exactly what was wrong with that one but that was in the first round of them I ever saw. Haven't ran into the situation again.
I do like to understand how these things work and I love to troubleshoot more than I actually like to fix.
#56
B
bk10s
B
bk10s
Getting back to this unit since we had a snowstorm today. Cranked forever to get it started. Fuel from cleaned out tank to filter through new line is low flowing. Fuel will not come out of filter unless I disconnect line and hold it down low. Then gas trickles out slowly. No gas getting to the pump. Maybe I will replace lines from filter to pump and pump to carb in case of vacuum leaks. Adjusted choke and I believe it is closing fully. Finally did start and ran good through wet, heavy snow on 3 driveways!there's an easy test. squirt some gas in the carb when cold and if it starts right up then you aren't getting enough gas. if this has a vacuum operated fuel pump, squirt the hoses where they connect to the pump with a little fuel / 2stroke oil mix. sometimes they suck air and even a little bit will keep it from pumping enough into your carb. It seals minor vacuum leaks. Most of y'all are over-thinking this problem.
Also, because of EPA the carbs run LEAN so any slight issue with the fuel pump will cause a hard-start problem. the reason it runs great after it starts is because it's creating more vacuum at the pump, overcoming the vacuum leak.
#57
B
bk10s
B
bk10s
Getting back to this unit since we had a snowstorm today. Cranked forever to get it started. Fuel from cleaned out tank to filter through new line is low flowing. Fuel will not come out of filter unless I disconnect line and hold it down low. Then gas trickles out slowly. No gas getting to the pump. Maybe I will replace lines from filter to pump and pump to carb in case of vacuum leaks. Adjusted choke and I believe it is closing fully. Finally did start and ran good through wet, heavy snow on 3 driveways!
#58
T
TobyU
T
TobyU
I still think your carb bowl is getting low/running out of fuel after it sits. If low flow was the problem, it would not run good after you get it started.
I always run my fingers around a bowl and in bottom after it's been parked for a few hours to see if fingers get wet from leaking gas.
I always run my fingers around a bowl and in bottom after it's been parked for a few hours to see if fingers get wet from leaking gas.
#59
mechanizm
mechanizm
this is generally because the fuel lines get dry allowing air into the system. the fuel pump can't pump if it's sucking air instead of fuel. I always squirt some gas in my mowers if they sat for a while ESPECIALLY in cold weather. This gets the fuel pump working faster overcoming a minor air leak. those fuel lines get brittle and don't seal well. after I get it thumping with fluid, i spray all of the connections with fuel/2stroke mix and that seals them.Getting back to this unit since we had a snowstorm today. Cranked forever to get it started.
#60
mechanizm
mechanizm
This is easy... don't go nuts doing a complicated test and "fix". It's obviously not getting gas which is the most common problem with lawn tractors because you use them then they sit for a while. the fuel line connections are likely leaking a little bit of air which causes your fuel pump to suck air instead of fuel. Do this test when it's cold after it sat for a while. squirt some starter fluid into the carb and I'll bet that it immediately thumps. this means that your engine is starving for fuel which is either the fuel pump OR (more likely) air leaking into the dry fuel lines not allowing your pump to suck fuel. I spray the connections of my fuel lines with gas/2stroke mix which seals them. this almost always solves my hard-start problem.Briggs 350777 Replaced plugs, coils, adjusted valves. Have to turn it over for 20-30 seconds to get it to start. Once started runs fantastic. What am I missing? Some kind of fuel problem? Replaced fuel pump a couple of years ago.
#61
mechanizm
mechanizm
when you put on the new filter you also reconnected the fuel line to the pump which sealed the air leak.When a took the fuel line off on the tank side of the filter, hardly any fuel came out. I blew out the line/backwards to tank and gas came gushing out (gravity). I put on a new filter and it started in about 1/2 a crank. Go figure. This engine has a fuel pump.
#62
B
bertsmobile1
B
bertsmobile1
Time to empty the fuel tank & clean the debris out that is plugging up the outlet just like hair clogs the shower drain, or used to when I had hair on my head .
#63
B
bk10s
B
bk10s
Here is my update. I finally replaced the fuel pump and fuel lines, including the pulse line to the valve cover. After sitting for a week, it started right up! Not sure if it was a failed 2 year old Briggs fuel pump or losing vacuum through a weak fuel line(s). This was definitely a journey, and thank you to all.
#64
mechanizm
mechanizm
it was a vacuum leak. next time you start it, squirt the fuel line connections with oil/gas mix in a spray bottle, which seals the lines from vacuum leaks. works like a charm. also the oil/gas mix can be used as starting fluid. I put a hole in my air cleaner cover so i can squirt the mixture into the carb to get my lawn tractor easily started. I then plug the hole with a bolt. works great. I do basically the same thing with my 62, C20.Here is my update. I finally replaced the fuel pump and fuel lines, including the pulse line to the valve cover. After sitting for a week, it started right up! Not sure if it was a failed 2 year old Briggs fuel pump or losing vacuum through a weak fuel line(s). This was definitely a journey, and thank you to all.
#65
T
TobyU
These things are fairly generic and you do not need the Briggs & Stratton brand one and a Briggs & Stratton box. Any of the plastic ones with the three ports do the same thing..
T
TobyU
It was the lines. Those fuel pumps hardly ever go bad and if they do they usually leak oil or gas all over the place and you know it. I hope you ordered one online for under $10 shipped and didn't buy one at a local parts store paying 50 or 80% more.Here is my update. I finally replaced the fuel pump and fuel lines, including the pulse line to the valve cover. After sitting for a week, it started right up! Not sure if it was a failed 2 year old Briggs fuel pump or losing vacuum through a weak fuel line(s). This was definitely a journey, and thank you to all.
These things are fairly generic and you do not need the Briggs & Stratton brand one and a Briggs & Stratton box. Any of the plastic ones with the three ports do the same thing..
#66
B
bk10s
B
bk10s
Circling back on this one. Full disclosure. So, I was struggling with the no start problem again. After going through EVERYTHING (including gas tank removal/cleaning, new fuel lines, new fuel pump, plugs, valve adjustment, etc. etc. etc.) I began to zero in on the carb. What did I find? THE FUEL SOLENOID WAS WORNOUT/INOPERABLE. So, I had to make a decision. The OEM Briggs replacement fuel solenoid is $147. The knockoff replacement carb WITH a new fuel solenoid is $33 with free shipping. What would you do? I bought the knockoff carb off Amazon and put it on. It was SIMPLE and the Briggs started instantly. Engine ran PERFECT right out of the box. Yea!!
#67
Scrubcadet10
Glad you got it going!
Scrubcadet10
you can also snip that plunger rod off. Won't hurt a thing. except a little pop *maybe* when you shut it off, occasionally.Circling back on this one. Full disclosure. So, I was struggling with the no start problem again. After going through EVERYTHING (including gas tank removal/cleaning, new fuel lines, new fuel pump, plugs, valve adjustment, etc. etc. etc.) I began to zero in on the carb. What did I find? THE FUEL SOLENOID WAS WORNOUT/INOPERABLE. So, I had to make a decision. The OEM Briggs replacement fuel solenoid is $147. The knockoff replacement carb WITH a new fuel solenoid is $33 with free shipping. What would you do? I bought the knockoff carb off Amazon and put it on. It was SIMPLE and the Briggs started instantly. Engine ran PERFECT right out of the box. Yea!!
Glad you got it going!
#68
T
TobyU
They were only 68 to 89 a few years ago and they were not available in the aftermarket at all.
Then, all of a sudden a few years ago they popped on eBay and then later Amazon coming with the carburetors but also by themselves for $7.95 to 10.95.
They are designed for two purposes that I know of. They act like it's to prevent them from popping after you shut off the engine but about 80% of the time they fail to even do that because many of these mowers with an operational solenoid will still pop quite often when you shut them off.
Then the second reason I think is the EPA really wants them to be on there because they don't want that fuel being unburned and going into the muffler and basically the air when you turn off your engine.
You'll find a good deal of them that have been snipped off with a pair of wire cutters and the engines are really no more likely to pop when you shut them off then before because like I said tons of them don't do their job anyways.
Kohler even issued a TSB for the after run pop or backfire as some people call it but it's not really a backfire, and it said to idle down the engine to your slow idle speed for 30 seconds before shutting it off..
I usually just add them down for about 8 or 10 seconds and that does the trick.
But yes.. that is the one I would buy too, the only problem here is this has been a gigantic thread and you've revisited multiple things multiple times to finally get back to the fact that it was not getting enough fuel as everyone said from the beginning.
Between 80 and 95% of the time plus every time you have a running issue or no start issue it boils down to that same thing that you're not getting enough fuel.
In the future remember that you can usually test that part by turning the key on and off and listening to it click or leaving the key on and hooking the wire to it on and off to see if it retracts but sometimes they will also get hot and break down so one way especially on those that will run a while and then stall out is to simply unscrew it and hold your finger on the bowl and hold the bowl on for a few seconds to see if it keeps running. If it does you know it's the solenoid.
It's down there impossible to find a bolt at the hardware store that will hold one of the bowls on to replace the solenoid but if you have a large selection of old carburetors you can usually find one or you have to basically get a bolt and a gasket and cut the bolt threads off shorter and smooth them out which I really don't recommend. Just take an old solenoid and snip off the end.
T
TobyU
For at least two decades I have been saying that the little anti backfire solenoid or after run solenoid or whatever you want to call that car solenoid is the most overpriced part on a lawn mower!Circling back on this one. Full disclosure. So, I was struggling with the no start problem again. After going through EVERYTHING (including gas tank removal/cleaning, new fuel lines, new fuel pump, plugs, valve adjustment, etc. etc. etc.) I began to zero in on the carb. What did I find? THE FUEL SOLENOID WAS WORNOUT/INOPERABLE. So, I had to make a decision. The OEM Briggs replacement fuel solenoid is $147. The knockoff replacement carb WITH a new fuel solenoid is $33 with free shipping. What would you do? I bought the knockoff carb off Amazon and put it on. It was SIMPLE and the Briggs started instantly. Engine ran PERFECT right out of the box. Yea!!
They were only 68 to 89 a few years ago and they were not available in the aftermarket at all.
Then, all of a sudden a few years ago they popped on eBay and then later Amazon coming with the carburetors but also by themselves for $7.95 to 10.95.
They are designed for two purposes that I know of. They act like it's to prevent them from popping after you shut off the engine but about 80% of the time they fail to even do that because many of these mowers with an operational solenoid will still pop quite often when you shut them off.
Then the second reason I think is the EPA really wants them to be on there because they don't want that fuel being unburned and going into the muffler and basically the air when you turn off your engine.
You'll find a good deal of them that have been snipped off with a pair of wire cutters and the engines are really no more likely to pop when you shut them off then before because like I said tons of them don't do their job anyways.
Kohler even issued a TSB for the after run pop or backfire as some people call it but it's not really a backfire, and it said to idle down the engine to your slow idle speed for 30 seconds before shutting it off..
I usually just add them down for about 8 or 10 seconds and that does the trick.
But yes.. that is the one I would buy too, the only problem here is this has been a gigantic thread and you've revisited multiple things multiple times to finally get back to the fact that it was not getting enough fuel as everyone said from the beginning.
Between 80 and 95% of the time plus every time you have a running issue or no start issue it boils down to that same thing that you're not getting enough fuel.
In the future remember that you can usually test that part by turning the key on and off and listening to it click or leaving the key on and hooking the wire to it on and off to see if it retracts but sometimes they will also get hot and break down so one way especially on those that will run a while and then stall out is to simply unscrew it and hold your finger on the bowl and hold the bowl on for a few seconds to see if it keeps running. If it does you know it's the solenoid.
It's down there impossible to find a bolt at the hardware store that will hold one of the bowls on to replace the solenoid but if you have a large selection of old carburetors you can usually find one or you have to basically get a bolt and a gasket and cut the bolt threads off shorter and smooth them out which I really don't recommend. Just take an old solenoid and snip off the end.