Interesting twist, need advice from the pro's

J

john in ohio

Active Member
I have a Husqvarna riding mower. Posted as white smoke when cold start.
History
I chased my tail for a couple weeks. Ended up getting a new carb and a new fuel pump. Still the same problem but now white smoke is constant!!

New effort.
I set up a gravity feed fuel line and removed the governor link to the carb, still white smoke and drinks a cup of gas in a very short time. Way to much gas going into the system!!
How, why!!
Sucks the gravity feed bottle dry very quickly, I tried it with two carburetors same results.
I removed the linkage to the governor, no change!!
What would do this??
What's the next step?
 
Sure does, I forgot to say that in my post. Had to replace the oil, twice in the last two weeks!
What is sucking that much gas? It's set up for gravity feed and disconnected the governor , so I could control the idle.
Most of the time, it runs fast even when the throttle is turned down all the way. Wouldn't it stall , or just run super slow,with the throttle closed, yet it runs very high rpm's, how!!??
 
. Sounds like you may have a blown governor. Start the engine with governor hooked up. Push the governor arm towards wide open throttle. It should push back against you. If not, it has a blown governor. Fuel in the crank case could have been from the previous carb. But replacing it should have cured that problem.





take
 
Was just messing with it, and it kind of holds the throttle near half throttle or greater. Then it moves and surges,and goes back to mid throttle or higher
 
The needle is leaking too much fuel into the engine when sitting. Even a new replacement carburetor can have problems, especially aftermarket. This thins the oil out and the piston rings cannot seal properly. The exhaust is literally spitting out the excess fuel with over thinned oil out of it.

The anti-backfire/ fuel shutoff solenoid is also likely stuck open and not operating.
 
White smoke + heavy fuel consumption usually means one of three things, and it sounds like you've already ruled out the most common (carb, pump):
  1. Crankcase fuel dilution. Pull the dipstick — does the oil smell strongly of gasoline or look watery? If yes, fuel is leaking past the rings or down a stuck intake valve into the crankcase, then getting burned off as white smoke. Common when a needle/seat fails internally on a Briggs intake valve.
  2. Stuck float (in BOTH carbs?). You said you tried two carburetors. If both behave the same, that suggests upstream fuel pressure is too high — the float can't seat properly. With gravity feed you'd think this is impossible, but check: is your fuel tank/bottle mounted way above the carb (high static head)? Try lowering the bottle to about 6" above the carb inlet.
  3. Cracked head gasket / failing valve seal. White smoke can be coolant-equivalent on air-cooled engines — meaning oil is being pulled into the combustion chamber via a head leak or shot valve seals. A compression test will tell you fast. If compression is below ~80 PSI it's heading toward rebuild territory.
Quick diagnostic: pull the spark plug. If it's wet with gas, carb/fuel issue. If it's wet with oil, valve seals or rings.
If it ends up being a head/ring issue on a residential Husqvarna riding mower, by the time you add up parts + labor a new mower often makes more sense — these engines aren't really designed to be rebuilt economically. I put together notes on current options that have actually held up reliably in this lawn mower comparison if you get to that decision point.
Run the compression test first — it'll save you another round of guessing.
 
kuldeepbaswal said:
White smoke + heavy fuel consumption usually means one of three things, and it sounds like you've already ruled out the most common (carb, pump):
  1. Crankcase fuel dilution. Pull the dipstick — does the oil smell strongly of gasoline or look watery? If yes, fuel is leaking past the rings or down a stuck intake valve into the crankcase, then getting burned off as white smoke. Common when a needle/seat fails internally on a Briggs intake valve.
  2. Stuck float (in BOTH carbs?). You said you tried two carburetors. If both behave the same, that suggests upstream fuel pressure is too high — the float can't seat properly. With gravity feed you'd think this is impossible, but check: is your fuel tank/bottle mounted way above the carb (high static head)? Try lowering the bottle to about 6" above the carb inlet.
  3. Cracked head gasket / failing valve seal. White smoke can be coolant-equivalent on air-cooled engines — meaning oil is being pulled into the combustion chamber via a head leak or shot valve seals. A compression test will tell you fast. If compression is below ~80 PSI it's heading toward rebuild territory.
Quick diagnostic: pull the spark plug. If it's wet with gas, carb/fuel issue. If it's wet with oil, valve seals or rings.
If it ends up being a head/ring issue on a residential Husqvarna riding mower, by the time you add up parts + labor a new mower often makes more sense — these engines aren't really designed to be rebuilt economically. I put together notes on current options that have actually held up reliably in this lawn mower comparison if you get to that decision point.
Run the compression test first — it'll save you another round of guessing.
Click to expand...
Thank you, this clears up some confusion. I did a compression test the other day and cylinder 1 is 100 psi and cylinder 2 is just over 100 maybe 105 psi. I forget what the plugs looked like, I'll recheck that today.
 
kuldeepbaswal said:
White smoke + heavy fuel consumption usually means one of three things, and it sounds like you've already ruled out the most common (carb, pump):
  1. Crankcase fuel dilution. Pull the dipstick — does the oil smell strongly of gasoline or look watery? If yes, fuel is leaking past the rings or down a stuck intake valve into the crankcase, then getting burned off as white smoke. Common when a needle/seat fails internally on a Briggs intake valve.
  2. Stuck float (in BOTH carbs?). You said you tried two carburetors. If both behave the same, that suggests upstream fuel pressure is too high — the float can't seat properly. With gravity feed you'd think this is impossible, but check: is your fuel tank/bottle mounted way above the carb (high static head)? Try lowering the bottle to about 6" above the carb inlet.
  3. Cracked head gasket / failing valve seal. White smoke can be coolant-equivalent on air-cooled engines — meaning oil is being pulled into the combustion chamber via a head leak or shot valve seals. A compression test will tell you fast. If compression is below ~80 PSI it's heading toward rebuild territory.
Quick diagnostic: pull the spark plug. If it's wet with gas, carb/fuel issue. If it's wet with oil, valve seals or rings.
If it ends up being a head/ring issue on a residential Husqvarna riding mower, by the time you add up parts + labor a new mower often makes more sense — these engines aren't really designed to be rebuilt economically. I put together notes on current options that have actually held up reliably in this lawn mower comparison if you get to that decision point.
Run the compression test first — it'll save you another round of guessing.
Click to expand...
The other day, I rechecked my valves. I have them around .004
If I can see them to get to top dead center of my stroke then they aren't hanging up, right? The valves are moving and good gap. Good compression around 100 to 105 psi. Can I still have a gasket issue? Don't get me wrong , I'm very new at this. Two years ago I didn't know the difference between 2 stroke and 4 stroke, I know now!
I'm watching the forum and grabbing all the info so I can see what to check next.
 
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