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Hi.

Wondering if anyone can assist in my crank, but no start issue. Have a gone through the various posts and applied suggestions...I have come up empty each time.

Problem: Mower cranks ok, but wont start up.

Mower has new battery and new replacement carb, new spark plug (RJ19LM)
I am getting spark. I pulled the spark plug and grounded looking for spark...saw good spark centered.
Curious, when looking at ignition and key, the leading edge has gap but looks like it touches the second piece (see attached). Wondering
if that is right...

I have checked the gap on valve tappets and they are set to .005 (both). I watched several videos and some said to find TDC and others said to make sure one is open and other closed and adjust each....I went that route and took the middle of the acceptable range.

I verified fuel is new and is flowing both in front of the gas filter as well as after. Dropped the bowl and there was fuel present (again brand new carb).

So the kicker is Mower will actually start briefly when a bit of gas is entered into the spark plug hole.

After that, it just keeps spinning...I am almost ready to give up on it, but was going to throw it out to the group to see if there was anyone who had this happen or might be able to help me further diagnose.

Thanks for your time.
Mike

The fact it runs with fuel poured down the plug hole means the ignition is fine, timing is OK and vales are ok.
Get some carb cleaner and spray a SMALL amount in the carb while cranking the engine.
If it starts, continue giving it SHORT SHOTS for carb cleaner for a minute or so.
If you can keep it running then you have a fuel delivery problem.
If it has a solenoid on the carb, pull it off and check that the plunger retracts when the mower is turned on.
If it has only 1 wire, the body will need to be grounded to check.

These solenoids are prone to corrosion, jambing from accumulated debris or burning out when the ignition is accidently left on for a long time .

Thanks for the reply and information. This carb has no solenoid and is brand new. I agree it seems to be a fuel issue but not sure where to look. I have purchased other carbs for push mowers and it was basically out of box and onto the mower...fired right up and ran great.

I will give the carb cleaner suggestion a try and see what happens...confused as i am getting gas into the bowl, so assuming its some adjustment on the carb?

Thank you.
Mike.

omerta14 said:

Thanks for the reply and information. This carb has no solenoid and is brand new. I agree it seems to be a fuel issue but not sure where to look. I have purchased other carbs for push mowers and it was basically out of box and onto the mower...fired right up and ran great.

I will give the carb cleaner suggestion a try and see what happens...confused as i am getting gas into the bowl, so assuming its some adjustment on the carb?

Thank you.
Mike.

Click to expand...

If the inlet valve is crook then an engine will fire a couple of times when you put fuel down the plug hole because it and some air is already in the cylinder.
If the same does not happen when you squirt fuel through the carb, then the inlet valve is crook.

If you can keep the engine running using an artifical carb ( the can of carb cleaner ) then the carb is crook.

Most carbs now come out of China.
Because the margins are so low there is not such thing as a defective carb.
The ones that get rejected by Briggs/ Kohler/ Honda/Ducar ec etc etc, get on sold to merchants who sell them on the web.
They get picked up by other online merchants and finally to you.
I see a lot of things like carbs with solid emulsion tubes, solid main jets, wrong floats, no float valve seat after the owners finally give up & bring them in .
If you did not buy it from a mower shop then there is no reason to expect it to work strait out of the box.

omerta14 said:

Hi.
Problem: Mower cranks ok, but wont start up.

Mike

Click to expand...

Just curious, if u take off the air filter and hold a sheet of paper over the air inlet and crank and while it is firing, does the paper flap up and down or only pulled down??

upupandaway said:

Just curious, if u take off the air filter and hold a sheet of paper over the air inlet and crank and while it is firing, does the paper flap up and down or only pulled down??

Click to expand...

OOh I like that one.
Another special tool to add to the call out tool kit.

bertsmobile1 said:

OOh I like that one.
Another special tool to add to the call out tool kit.

Click to expand...

Use only Briggs and Stratton paper. I did this to quick test(and later would fix) for warped valves or valves not closing in general etc.
quicker than taking the head off and checking.

upupandaway said:

Use only Briggs and Stratton paper. I did this to quick test(and later would fix) for warped valves or valves not closing in general etc.
quicker than taking the head off and checking.

Click to expand...

Like everyone else I am here to learn, which is why i came here in the first place and every piece of information and different way of doing things is some good leaarning, for which I duely thank you.

bertsmobile1 said:

Like everyone else I am here to learn, which is why i came here in the first place and every piece of information and different way of doing things is some good leaarning, for which I duely thank you.

Click to expand...

Yes agree...I really enjoy the challenge of fixing things. I could have purchased a new mower but wanted to bring this ol girl back to life. I will try the paper trick and see what happens. Of course last night while trying the carb spray suggestion, the flywheel spun and hit the ignition module breaking one of the posts. Guess i should have know that would happen based on my post (with pictures mind you) showing it off kilter a bit.

So i think I will need to be looking for cylinder block now since one of the posts was broken off...nothing like getting thrown in head first :thumbsup:

Appreciate people taking the time to respond!
Mike.

bertsmobile1 said:

Like everyone else I am here to learn, which is why i came here in the first place and every piece of information and different way of doing things is some good leaarning, for which I duely thank you.

Click to expand...

Oh you don't know how much i mess around... While i don't repair OPE for a living, they are the source for all my rental buildings' OPE. Don't know why but for the 4 Briggs 12.5hp found i needed to use this trick to check and later confirmed the intake valves warped. I even used this for a Komatsu trimmer where it has 130 compression but it won't stay running. It was because the lower cyl was shot- air was blowing back out the intake thus too low compression in the lower chamber. Don't get me started on car engine part modifications....

"I really enjoy the challenge of fixing things."
omerta14- for starters, u can run the valve seal test without the ignition coil- obviously it just won't fire but it might tell u why it won't start. If u *REALLY* want to fiddle more with it, I actually came across a 10hp tecumseh similar to yours (just no OHV) where the ignition coil post also broke off. If there is some post left, on mine i filed it down just so it is flat and tapped the post (be careful not to drill through into the cylinder) and added a spacer. Get longer (10-24??) screw thus 2nd post back to hold the coil. I used it for a few years(left it with the apt building when i sold it.) If you can find someone, u can also weld on the broken piece (shows welding is the one equip i dont have).

upupandaway said:

"I really enjoy the challenge of fixing things."
omerta14- for starters, u can run the valve seal test without the ignition coil- obviously it just won't fire but it might tell u why it won't start. If u *REALLY* want to fiddle more with it, I actually came across a 10hp tecumseh similar to yours (just no OHV) where the ignition coil post also broke off. If there is some post left, on mine i filed it down just so it is flat and tapped the post (be careful not to drill through into the cylinder) and added a spacer. Get longer (10-24??) screw thus 2nd post back to hold the coil. I used it for a few years(left it with the apt building when i sold it.) If you can find someone, u can also weld on the broken piece (shows welding is the one equip i dont have).

Click to expand...

Like the *REALLY* in your reply...When I saw that post brake I almost tossed in the towel lol. I like the idea of trying to flatten out the post and tap... will test the valve seal as mentioned because if that is hosed, not sure its worth pursuing this any further...

Thanks for your feedback.
Mike.

omerta14 said:

Like the *REALLY* in your reply...When I saw that post brake I almost tossed in the towel lol. I like the idea of trying to flatten out the post and tap... will test the valve seal as mentioned because if that is hosed, not sure its worth pursuing this any further...

Thanks for your feedback.
Mike.

Click to expand...

UPDATE: I was able to flatten both broken posts and tap a bolt into each one....the ignition took a beating when it hit, so I replaced. I gapped it to .012". Tried using the specialized paper tool and noticed that I was only getting suction, no blowing upwards.

poured some gas into the spark plug hole and tried to fire it....took several cranks, but it fired up. Now it was running but rough...periodic air bursts back up into the air cleaner......Took it for a spin, but it did not have a lot of RPM and sounded like it would die a couple of times. However I was able to engage the deck and cut a small section of my lawn....

Didn't want to push it to much first time...So not really sure if this is an adjustment of some kind to get the motor roaring or she might be on her last legs...any suggestions on what I might be able to do?

Thank you for your help so far...although it was rough at times, it was nice to get this thing cutting!

Mike

omerta14 said:

.Now it was running but rough...periodic air bursts back up into the air cleaner......
Mike

Click to expand...

Half way there....

I forget if u did, but check if the flywheel key is good and not sheared. Being off a hair can cause your problem.

btw, when u run, it won't reach full speed? if when running and "spitting back", do u see a puddle of gas at the bottom on the intake "throat"??
If Y and your carb bowl has an adjust screw, try adjusting it lean. Too rich will slow the motor...

Occasional sputter\slow can be by too rich, but bfore tearing it and checking if the valves are closing\sealing\gapped properly again try this.
Good luck.

Bert I thought everybody knew about that paper trick..........

Yeah right Bull Butter....... I didn't know that either.... Saves time for a quick test and then BREAK out the leak down tester............

Thanks Up and away ~!~!

Plus Tard Mes Amies ~!~!