Here's the deal, I found this Lawn Boy 7035 in a barn in VA. I suspected that it wouldn't start and I was right. I cleaned the carb out to the best of my abilities, confirmed that it indeed had spark, confirmed the presence of good compression, and made sure that the pull starter was working. After many pulls, all I can get out of it are one or two tiny pops before it dies. I'm pretty sure that it backfired once because it gave a loud bang and a puff of white smoke after quite a lot of starting fluid in the carb. I read that it might be a muffler issue but I can't get the plate the blade mounts to off to check. I'm no Lawn Boy expert so I hope one of you could help me out. Thanks!
Engine Lawn Boy 7035 (1986) starting problem
- Thread starter rowen211
- Start date
One more thing, when I open up the fuel valve, fuel starts to leak from the carb at a pretty fast drip. I'm not sure if it has anything to do with the float or needle valve but they looked OK when I checked them.
ironhorse
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you still have a carb issue, i would replace the float and the inlet assy., it's most likely so flooded it's not going to start, gotta get the carb fixed before moving on to possible other issues (sheared flywheel key, fouled sparkplug, crank seals), good luck with it:wink:
Two-Stroke
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You've got a problem with the float valve. It must close completely when the bowl is full. Try cleaning it (I like compressed air for things like that). If you can't fix the problem by cleaning, you may have to replace the valve and seat.
The engine will run WAY too rich if the float valve is messed up like this.
Fireman 123
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If you still have the backfiring issue after addressing carb problems first, check for a sheared flywheel key like earlier mentioned. I had one that drove me nuts trying to get to run right until I noticed the key was sheared. Good luck
It turns out that the problem is both the flywheel key AND the carb. I looked at the flywheel and noticed that magnet that generates power for the spark plug was nowhere near the coil when it should be so I pulled the flywheel off, and the key was indeed sheered. After replacement, it finally ran after who knows how long. Ran really well too. But half the fuel I used poured out of the carb (leaving a stain on my front walk), when the other half actually went into the combustion chamber. I don't understand how it could run so well and still have this problem.
Well, we do have many antique mowers here..
There fuel systems have trouble with the ethanol in the gas.
At ACE hardware, there is (I think) "Mechanic in a can" for this...just another fuel additive..better? than Stab-il...
We need a good method to clean and re-seat the fuel in-let valve (needle and seat).
There fuel systems have trouble with the ethanol in the gas.
At ACE hardware, there is (I think) "Mechanic in a can" for this...just another fuel additive..better? than Stab-il...
We need a good method to clean and re-seat the fuel in-let valve (needle and seat).