High idle hunting and back firing on FrankenDeere snowblower

[harringtondav]

Years ago I replaced the Tecumseh 5 hp Sno King engine on my snowblower with an 8 hp Tecumseh. It took some work to get the governor and linkage to maintain power and high idle under load.

Problem is when I'm at no-load high idle the engine starts to hunt and surge, backfiring between surges.

Any suggestions to maintain a constant high idle speed?

 

[82rude]

Just went through the same exact issue.On the side of the carb there should be a air jet needle that you can screw out and clean.I said the heck with that and ordered a new carb from amazon for less than 20 dollars cnd.Problem solved .For approx. 13 or so American dollars why even fool around with an old carb?Mine was a 2005 8hp Tecumseh.Carb is iztor carb .Get your model number for the motor and go from there.

 

[tpenfield]

^^^ agreed. Hunting is usually a fuel related problem and the quickest fix may be a new carb.

FWIW - I had an Ariens with the 8 hp flathead Tecumseh engine (318cc) with similar issues and a carb replacement ( adjustable style carb ) fixed it for the most part, but the engine would still hunt a bit at high idle, especially when cold.

It was OK since the normal operation is either at/near full throttle or at low idle - both of which were fine.

 

[MTboatguy]

The air jet in my snow blower is a plastic non adjustable, unfortunately it is not the right size for the altitude I live at, I have read that a bunch of guys with the same blower I have, have had to drill the plastic air jet to get them to stop surging. When I am blowing snow it runs smooth, but at idle it hunts and has since the day I purchased it 5 years ago.

 

[82rude]

update?

 

[Scott Danforth]

Dirty carb (running lean)

 

[harringtondav]

update?

I've got your Iztor info penciled down. I switched over to R&R the starter in my 20 yr old Durango. And that's been a barrel of laughs. Had to grind off two rusted cross member bolts to gain access. Now can't budge the top starter retaining cap screw.

I'll either turn it over to a shop, assuming I can click the solenoid enough for one last start. If not, I'll have to add a tow to the tab. My 600 ft/lb air impact gun won't touch the bolt. For $200 min shop charge + a possible tow, I'm shopping for a beefier impact gun that will squeeze over the frame for <= $200. MAP gas on a propane torch didn't help. I've got a mini map/oxy torch that gets plenty hot. Pretty sure the shop will use a oxy/acetylene rosebud.