Outdoor Power Equipment and Small Engines - Sears snowblower

Hello.

My snowblower has recently started to backfire, and there are sparks and flames coming out of the muffler. The muffler gets cherry red after a couple of minutes. Does anybody know what the problem could be?

Thanks.

Laurent

Lean
Could be a clogged vent on the gas cap.--- Turn off machine, open gas cap and put back on to let in air, then retry blower.
Or

Could be small piece of of ice in the carb blocking the gas in the tiny ports.--- Put some deicer in the tank and wait for a while for it work then retry.

Or

Could be a loose carburetor ot bad carb mounting gasket.----Look and wiggle carb for looseness, also look for signs of wetness where carb joins to engine.

Or

Could be some one played with the jets--??????

Or

Could be dirt in carb---Not going there yet

So

WARNING

Don't run it in those conditions or its going to melt something. You know that.
I find its mostly water and ice so I recommend to start with the simple things.
Let us know if those don't work

It would help to know some more about what you have for equipment. Post back with the make and model and serial of the machine and, more importantly in your case, the engine make and ID numbers from such. Chances are you have a main jet that needs to be cleaned out as it appears you have a lean carburetor issue.

Thanks for the reply. It's a Sears Craftsman Dual Stage Snowblower, model C950-52950-0, 11HP, serial no.74210110CJ00010. It has a Tecumseh 4 cycle engine 143.001103. I have the owner's manual for the parts. It runs fine, but lately it seems to be stuck in running at full speed. And now it coughs and there are sparks and flames coming out. The muffler got real red, so I turned it off. I though perhaps the muffler was finished, so I replaced it. The old muffler was rusted and kinda cheap anyway. The replacement muffler seems to be of better quality. Anyhow, I don't have any skills in fixing small motors, but if this is simple enough, I think I'll try.

With little experience with small engines, I'd recommend buying a new main jet/carburetor bowl nut and replacing yours rather than attempt to clean yours out. The Tecumseh part number for the jet is 640012 and is less than $5. To replace such, shut off the fuel supply via the fuel valve under the gas tank, run the engine to allow the fuel in the carb and fuel line to be used up, using a 1/2" wrench remove the jet from the carb bowl and install the new jet along with a new gasket, part number 27110A. If you have no fuel valve you'll want to pinch off the fuel line in some manner so as not to damage the fuel line and also, have a shop towel under the carburetor when removing the jet as some fuel will still be left in the bowl. Any local Tecumseh dealer in your area should have these parts.

Thanks puey. I'll try that.