Sears snow thrower with Chinese engine, surging then dies

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

fespo

Minister of Fire
Dec 14, 2005
730
South West burbs of Chicago
Im completely frustrated with this engine, I have tried everything I can think of. The snow blower is not mine and only used 1 TIME. They left gas in over the summer and messed everything up. A new carb was installed, opened up the jet, tried moving governor linkage around, new fuel line, clean in tank filter, new plug, only fresh gas, remove cap for vapor lock, Engine will start and run about 10 seconds then seconds then start surging with choke on then dies if you shut of choke . All gasket are in great shape, there is nothing I can see that is missing or broke. TIA Fespo
 
Float level too low, running lean when it dies? Does it run longer with half choke on? Or can you keep it running giving it some choke to give it more fuel?
With bowl off, carefully raise float until it stops. (closed needle and seat) The float is normally about level when closed.
 
  • Like
Reactions: fbelec
  • Like
Reactions: fespo
Does this engine have a fuel pump of is it gravity fed?
 
I suspect that by "shut off" above @fespo means "disengaging" the choke, that is, opening the butterfly.

Probably, but it doesn't hurt to make sure.
 
First thing I would do is a close inspection of the impulse line. It goes from the crankcase to the carb. If it has air leak or is not in good condition the engine well act exactly like you are describing.
 
You said you moved the governor linkage around. If the spring isn't right or the linkage is off, it can flap back and forth and cause those symptoms as well. It's obvious if you look at the linkage when it's running though, as the throttle will be opening and closing, and eventually can close completely, killing the engine. But still sounds like a fuel delivery problem. I've also had DOA cheap replacement carbs.
 
make sure the mixture screw is at 1.5 turns out from bottomed out (all the way screwed in) then go from there. also when it dies quickly clamp the fuel line so that you can recheck the float level when it died out. if the fuel is filling the fuel bowl slow it might look ok when checked after a while but if it filling the bowl slow it might not be getting enough fuel to run.