jayboy13

My MTD 22" 2 stage blower with a Techumsa 5 hp doesn't work like is used to. It is about 5 yrs old. It's had regular maintenence, oil changed every year and oil checked regularly. (level is rarely down). Spark plug changed this year. At the end of every winter, it's had Stabil added to gas and never failed to start the first time next season. Auger belt was replaced a couple years ago.

Other than "being tired", here are my observations/symptoms:

Compression feels good.

It will start but not as easilly last year.

After a few pulls with full choke it is necessary to put choke to 3/4 or 1/2 before it will start.

After taking off choke, it revs up normally

If it is idling, moving throttle to fast revs up quickly

Gas cap breather is open and clear.

Operation:

If the snow is light and fluffy, it will blow it fine

Once in deeper snow, rpms fall down. I can hear the governor give it power, but it still slows down.

If i ease up, the engine will resume speed.

If I don't ease up, it will stall.

Restarting takes quite a few pulls

Something I noted this year, when I'm done using it, it will backfire when I push the throttle to off.

I read a post on another forum that the flywheel woodruff key might be sheered and timing off a few degrees. I'm not sure if this is the case and haven't checked it. I've also seen post suggesting the carb might be dirty. I added some fuel injection cleaner to the tank several tankfulls ago and it didn't make a difference.

Any help appreciated.

MrChooks

Hi jayboy and welcome to TSF and Tks for the detailed thread - the more info, the better

OK, given that you machine is just not as powerful as it was, but otherwise starts and runs OK, I'm thinking of 3 possibles.

1/ The back fires on revving down is a symptom of the float level being slightly off. Might be a bit of muck in the needle valve or the float itself. Maybe a "manual clean" of the carb and check and re-adjust of the float will take care of this.

2/ Is the "driven-end" of your machine jamming up or overly tight. If bearings or moving part (auger) clearances become too tight - they can reflect in using a lot of engine power. With all clutches disengaged - can you pull the moving parts through and do they feel "free to move" without any binding?

3/ If all the above are OK, it might be that the engine is just getting tired / old but as you seem to be taking good care of it and it's only 5 years old - I would be surprised if that were the case.

So, see how you go with a proper carb clean and readjust and a look at any moving parts binding issues.

K-B

I think I would do a carb rebuild or at least a disassembly, inspection and cleaning, first of all.