Snow-thrower performance issue

[Scutter01]

I have a new-ish two-stage Yard Machine snow thrower that seems to struggle and bog down even on relatively light loads. If the snow is wet or thick, forget it. Even on the lowest forward setting, I'm still stopping every foot or so and letting the engine recover so it doesn't stall out. Stalling requires dragging it back to the garage to use the electric start because the pull-start is out of the question (even on an engine that's been running). After it bogs down and dies, starting it usually causes a backfire (really an after-fire, as it seems to be at the muffler, not the cylinder).

Any idea what the causes could be or how I can troubleshoot/remedy? This is a pretty decent snow thrower. It shouldn't be having this much trouble getting through snow.

 

[tom1025]

I would start by checking the air filter and spark plug.

 

[6birds]

Fresh gas? Recent check on the air cleaner? New spark plug? Fuel/Air/Spark, check tha basics first. My guess is weak spark under load, but only if the first 3 a perfect.

 

[Dave Doehrman]

Any idea what the causes could be or how I can troubleshoot/remedy? This is a pretty decent snow thrower. It shouldn't be having this much trouble getting through snow.

I have a 3 year old Toro with an 8 hp Briggs and had the same problem this fall. I drain the gas and lube the cylinder with oil every spring when I store it for the summer. I put fresh gas with Stabil engine treatment in, but it lacked power and constantly backfired while running. The exhaust smelled like it was running too rich.

I pulled the carb cover and sprayed carb cleaner into the inlet with the engine running. There was a screw on the side of the carb that I thought was the mixture screw, but it was completely seated. I backed the screw out a little with the engine running but it didn't change anything. I pulled the screw out and sprayed some more carb cleaner in the hole and it seemed to help. I put the carb screw back in and then I noticed two screws on the throttle linkage for max engine speed and governor operation. I backed the max engine speed out a little and put a little more tension on the governor spring.

After running for a few minutes the engine smoothed out and the backfiring stopped. Mine has a six forward speed gearbox. In the past I could keep up with the machine in 6th gear. I put it in 5th and engaged the drive and darn near ended up on my face. I can't keep up with it in 5th anymore and the engine has more power than it did when I bought it new. Don't go wild on the governor screw or you'll be blowing engine parts instead of snow, but it sure perked up my blower this year. I was blasting through 8-10 inches of wet heavy snow in third gear last weekend.

Good luck... I'm guessing it just needs a little carb cleaner and maybe a little adjustment on the throttle linkage.

 

[dice dealer]

Sounds like somthing simple ....Check what everyone else has said ..all good ideas....
If none work , Pull muffler off see if it has a piece of screen type material behind it (spark arrester ) .
IF it does have this it may be starting to get Clogged ...
if its clogged clean it by heating it with a propane torch till cherry red , tap it against something to knock all the crap off it ..

Again yours may not even have this in it (some don't) .

but the problems everyone else have told you wil cause this screen to clog if yours has it .

 

[eldirector]

Back on topic for a moment.... Does the thrower have a choke on it? I have to run mine with the choke slightly closed, especially when it is this cold out. It will bog down otherwise.

Like others have said - it is usually something simple.

 

[Scutter01]

If it weren't practically brand new, I'd be taking a much harder look at a possible gunked up carb/air filter/sparkplug, etc. I can certainly check the mixture though. Eldirector, it's not the choke, as far as I can tell. If I had to hazard a guess, I'd say it's not burning all of the gas, which is what's causing the afterfire.

 

[kwatters]

If it weren't practically brand new, I'd be taking a much harder look at a possible gunked up carb/air filter/sparkplug, etc. I can certainly check the mixture though. Eldirector, it's not the choke, as far as I can tell. If I had to hazard a guess, I'd say it's not burning all of the gas, which is what's causing the afterfire.

Just because it is new doesn't mean the carb isn't malfunctioning. could be dirt from the factory.

 

[Scutter01]

I need a small-engine guy. Between my tractor and now my snow blower, this is getting old.

 

[Dave Doehrman]

I need a small-engine guy. Between my tractor and now my snow blower, this is getting old.

Why would you want a midget mechanic ???? Can they get closer to their work?

Seriously, I had a 5 hp blower before I got the new 8 hp model. It ran like crap the first time I tried to use it. They had to clean the carb and replace the gas tank on a brand new machine. Said there was paint on the inside of the tank that gunked up the carb.

 

[mrjarrell]

I need a small-engine guy. Between my tractor and now my snow blower, this is getting old.

Try Campbell's on S. 8th street in Noblesville. 773-6727

 

[ironjaw]

I need a small-engine guy. Between my tractor and now my snow blower, this is getting old.

I'm not a pro by any means, but I'm off work already and I could come look at it for you.

 

[Andre46996]

Every small engine from the factory is preset to run rich, this helps them to make life expectancy claims. Whether it is a chain saw, weed eater, push mower, rider, snow thrower, etc.. It is even worse for 2-stroke motors.

I could explain to you what do to and how to get it set properly but if you have any warranty it will void it.

PM me the model number so I can see a carb diagram and if if want I can explain to you how to sent the mixture adjustment needles. You will need to be at least somewhat mechanically inclined for this.

The after stall pop is unburned fuel that accumulated in the cylinder and muffler after it stalled.

 

[HandK]

Sounds to me like the carb is running rich!! if you have no power and it's hard to start, there should be a screw on the bottom of the carb, run it all the way in and then back out 2 1/2 turns it should get you real close to factory settings!! you should notice it having more power afterwards.

 

[ironjaw]

I was kind of thinking the choke was stuck on......

 

[public servant]

Sounds to me like the carb is running rich!! if you have no power and it's hard to start, there should be a screw on the bottom of the carb, run it all the way in and then back out 2 1/2 turns it should get you real close to factory settings!! you should notice it having more power afterwards.

Once you get it running, adjust it as you start putting a load on the engine. It should be pretty easy to get it to the right setting. I had to do this to mine last week. A quarter turn this way...a half turn that way...until you find just the right setting.

Of course mine's about 30 years old...but it still throws snow all the way into the neighbor's driveway.

 

[Scutter01]

Now I'm torn. Do I hope for more snow so I can work on my snow thrower, or continue to hope for an early spring?

 

[public servant]

Now I'm torn. Do I hope for more snow so I can work on my snow thrower, or continue to hope for an early spring?

You can fix that "B" word next year.

 

[Naptown]

at least it has been a mild winter and this hasn't really annoyed you.

 

[tom1025]

If its a two stroke I would still check the spark plug. It dosnt take much to fowl one if your fuel and oil mixture is off.