MTD Snowblower bogging down under load

[MuskyJoe]

Originally Posted By: hemitom
Originally Posted By: kschachn
Originally Posted By: MuskyJoe
Originally Posted By: hemitom
does this carb have the power adjusting screwing on the bottom of the carb. ?? if it does i'm willing to bet its out of adjustment.

It does have the adjusting screw on the bottom of the carb. will mess with this over the next couple days as well.

Not to question your competency or intelligence, but it isn't the "screw" on the bottom of the carb bowl that's used to drain fuel, right?

I likely have the same snow thrower as you do (mine is 17 years old) and I just went through a complete rebuild this past summer. I'd look at the governor too just to make sure it is linked up correctly.

No some older machines have a power adjusting screw on the bottom of the float bowl uasually bogging under load can be fixed by adjusting the screw. You are correct most new blowers have the drain fixed to the float bowl .


Correct, mine has the float adjustment screw and the fuel drain also. made some adjustments today and will have to wait until Friday to test it under load of throwing snow to see if it still bogs down.

 

[hemitom]

Thats the only way to set it up is under load, usually takes a few passes to hit the sweet spot.

 

[JTK]

Tecumseh snow king flat head engine I presume? I'm assuming it doesn't bog down when you engage the auger and wheel drive when not under load? If so, like said, it's a carburetor issue. You can mess with it, but I'd get a spare off eBay or the likes to have on hand to swap out. Unless it's just a bowl drop, I typically don't mess with cheap OPE carbs. I just replace them. Expensive or rare stuff? Absolutely I'll tear into it if need be.

 

[SHOZ]

I asked about the motor but I don't think is was said what it was.

I had a Tecumseh snow king do the bogging down thing, it needed choke to keep running. Turned out to be the crank key was almost sheared off.

 

[JTK]

^ Good point Shoz. Could be a flywheel key too. Kind of a rare issue to have on a snowblower engine, but you never know when it comes to mechanical things.

 

[Matt6127]

Originally Posted By: MuskyJoe
I have a 14 year old MTD 2 stage snowblower that I did some work to in the off season (replaced carb, fuel lines, spark plugs, belts and cosmetic work). The snowblower starts right up and seems to run very well with a lot of power in idle and under very light snow. As soon as I get into a couple inches of snow (this past weekend was very dry and light) the snowblower bogs down and I have to let off the throttle to let the thrower catch up so it does not bog down and die. I do plan on lubricating the discharge chute tonight to eliminate that as a culprit but I am wondering if anyone can offer tuning advice for the machine to be more efficient in deeper snow. This problem is especially frustrating at the bottom of the driveway after the plow comes through. Any advice is so greatly appreciated.

Joe in Wisconsin


I would do a UOA just to be safe...

 

[MuskyJoe]

Originally Posted By: JTK
Tecumseh snow king flat head engine I presume? I'm assuming it doesn't bog down when you engage the auger and wheel drive when not under load? If so, like said, it's a carburetor issue. You can mess with it, but I'd get a spare off eBay or the likes to have on hand to swap out. Unless it's just a bowl drop, I typically don't mess with cheap OPE carbs. I just replace them. Expensive or rare stuff? Absolutely I'll tear into it if need be.


nothing seemed to fully fix the problem. the Auger belt was a little loose and that did seem to help with throwing speed and distance but it was still bogging down. Had plenty of snow this weekend to mess with it. Ordering a new carburetor today and replacing it as I believe it is an issue with the carb not working correctly. Thanks again everyone for the help and suggestions.

 

[Rick in PA]

I'd toss in checking the compression. I've had similar loss of power / hard starting problems with my lawn mower that were fixed with a little work on the valves.

A buddy at work had just the problem you describe with his snow blower. It turned out the valve lash was too tight. He lapped the valves and ground the stems a bit to get the correct valve lash and that fixed his problem.

 

[FastLane]

I would check compression as well. If not the carb. Buy a Chinese carb off Amazon. I just replaced mine. I reused the original jets since the China carb was running way too rich. Old Tecumseh is running awesome now.

 

[Cujet]

 

[dblshock]

malined governer will act like that.

 

[yeehaw1960]

Have you checked the compression yet. Use your natural (poor man's) compression checker. Take the plug out and put your thumb over the hole. Does the compression convincingly push your thumb off the plug hole when you sharply pull the rope? If not, it's a worn out motor or you (could) have a valve problem.

AND, more and more on Briggs and Tecumseh engines, I'm finding that the seat (as in needle and seat) swells up and makes the fuel check off too fast. Thus, you literally run out of gas under heavier load. Pull the bowl and note the float's position when you lift it up and the needle makes contact with the seat. Seem like it would be pretty close to the bottom of the bowl if assembled? Ah Ha!

Ho Ho Ho