Hi guys. This morning i fired increase the lawn tractor v no problem. I was cutting the grass because that 15 minutes and also the engine died. Ns tried number of time to restart and also finally gained it running. Climate it ran actual rough and also was backfiring thru the carb. I confirm the crankshaft an essential and it was fine. I confirm the fuel plunger solenoid and it is working properly. I placed fuel injector cleaner in the tank, sprayed carb cleaner when trying come start and also it is tho backfiring thru carb. I did no cut any kind of thick grass or fight anything through the blades. Strange....just did this out of the blue. The recent tune up on the lawn tractor was done this spring and also has around 8 hours run time. Fuel filter, waiting filter, and oil change. You re welcome help. :shrug:The lawn tractor is a Sears LT200020 HP OHV Briggs engineMODEL# 31P977TYPE-0575CODE- 060208ZE
Bill SherlockSubscriber
A problem with the fuel pump deserve to cause ago firing with the carburetor because of insufficient fuel flow. I"d check the fuel line for a cracked or pin hole also.Bill

I think Briggs OHV engines are pretty finicky about valve (rocker arm) clearance. If intake is not closing fully, you might get backfire.

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Bill Sherlock said:
A difficulty with the fuel pump have the right to cause earlier firing with the carburetor due to insufficient fuel flow. I"d inspect the fuel line because that a cracked or pin hole also.Bill
Thanks Bill,I don"t have a fuel pump however I have the right to easily check the fuel line. Over there is around 20" the fuel line.
Those engines are infamous for valve issues.....valve seat coming loosened from the head, and also valve travel guide coming loose and relocating up versus the retainer. As soon as this happens, it"s frequently caused by overheating. Plenty of times due to a mouse swarm under the shrouding.
I replaced all the fuel line and also fuel filter. If looking about I noticed that the space on the ignition coil to be .014 ~ above one side and .002 on the other. Ns don"t understand what the correct gap is. Carry out you know what the space should be and could this be the factor for the backfire issues??
I collection the void on the ignition coil to 0.010 top top both sides. Ns disconnected the tiny ground/stop wire to the coil also. I tried firing up the beast and I acquire the very same results. Naught changed. Dang.
---------- Post added at 05:21 pm ---------- Previous article was at 05:13 afternoon ----------
Those engines are well known for valve issues.....valve seat coming loosened from the head, and also valve guides coming loose and relocating up against the retainer. As soon as this happens, it"s regularly caused through overheating. Plenty of times because of a mouse swarm under the shrouding.

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Thanks because that the reply. Ns didn"t take it the valve cover off yet. I keep the motor an extremely clean. I constantly blow turn off the grass clippings B4 I placed it away. I"m hoping its no the valves. The an equipment is fine maintained and also prob has around only 40 hours on it. Bumber.
Sounds like a carb issue. Take it the optimal off the carb and also look around. New ethanol fuel work something loose, partially clogging a jet, needle/seat?