Snowthrow woe

[thelews]

Perhaps you guys have an idea of the problem.

Small, old (20+ year) Toro, single stage snowthrower starts, runs for about 3 seconds, backfires (just kind of a pop) and then quits. This can be repeated indefinitely, but it will not stay running.

This problem started at the end of last winter and I forgot about it all summer. Otherwise, this snowthrower has been a perennial champ.

I haven't dug into it yet, but thought maybe someone would know the problem and I could short circuit the fix.

Thanks.

 

[OccupantRJ]

The backfire indicates to me that the fuel mixture is leaning out after starting, which makes the popping. The carb jet(s) may be partially clogged. A partialy clogged fuel filter could also cause this, allowing enough fuel for starting, but not allowing enough to continue flowing, thereby leaning the mixture. Test the theory by spraying a shot of wd-40 into the intake about time you think it is going to die, to see if it runs longer. If so, it's fuel related. Is it backfiring out of the intake, or the exhaust?

 

[thelews]

I'm going to say out of the intake, it's on the side near the top and I can see it, while I'm pretty sure the exhaust is down near the pallets. I haven't dug into this at all yet, but, it is consistent with lean conditions I've experienced with cars and backfiring through the carbs. I'll have to pull it apart and clean things out.

Thanks.

 

[Rentawrench]

Take the carb off an Clean it .

this is a product of E10, the ethnol gums up the inside of passages in the carb.

they say the shelf life of E10 is 3 months, so dump the gas in your car an buy fresh gas

for storage of Anything gas powered use some racing gas

 

[Buckgnarly]

A partialy clogged fuel filter could also cause this, allowing enough fuel for starting, but not allowing enough to continue flowing, thereby leaning the mixture. Test the theory by spraying a shot of wd-40 into the intake about time you think it is going to die, to see if it runs longer. If so, it's fuel related. Is it backfiring out of the intake, or the exhaust?

Or fuel line. Same thing was happening to my friend's riding mower. I took apart the carb, soaked, cleaned, repeated. Nothing worked.
Finally took a look at the tank...we have lady bug type beetles that cluster in the winter, somehow they got in the tank. Took apart the rubber fuel lines, blasted them out with air. Enough fuel made it past the blockage to start, but would die shortly there after. Stupid mower ran like a champ after that.

 

[Red Green]

I had the same issue on my dad's honda powered pressure washer. The jet was clogged.

 

[slopecarver]

Is it a 2-stroke or 4-stroke? Clean the carb and tank, Check the plug, find a manual for your model somewhere online and look at the factory carb settings for high needle/low needle/idle