# Noob here, help with old MTD/Tecumseh engine issue



## James R (Feb 2, 2021)

8HP 26" old MTD. HMSK80 155545U. Probably was new in 1996.. I'm the original owner. I use Stabil in it just before spring and then run it dry each year before putting it away. It gets an oil change each winter and then usually starts up on one pull. it still starts on one pull but runs real rough for about 10 seconds before smoothening out. 
It has fresh fuel in it. Fuel lines are good, replaced it last year. Has an issue now where it just keeps stalling as soon as it has any sort of load to it.
Sometimes it just stalls out when engaging the auger without any snow in the chute. 
Auger spins free by hand, not obstructions or restrictions.
But then sometimes i can keep it running and then put some load on it and it runs fine, throws snow well, then 5 minutes later it will just start oscillating, sputter and die. Starts back up with one pull but takes a bit for it to run smooth again.
I know that compression tests are subject to opinion here but i did one anyway using the electric start. it maxes out at 60 psi. Good? bad? 
I pulled the carb and cleaned everything out, looked clean in there. Tried adjusting main jet on the bottom of the bowl. that made no difference. Governor and all linkage looks fine. Spark plug looks a tad rich but maybe that is because it keeps stalling out and running like garbage. I'm tying to clean up this 2 feet+ of snow we just got here in PA and it is a nightmare trying to keep it running. What could possibly be wrong with this thing? 
I'm desperate here. I'd even consider a motor swap. is there a direct replacement for the 155545U?


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## ST1100A (Feb 7, 2015)

Your float level could be to 'Low' causing it to die out when it needs the extra fuel when it comes under a load.
That happens when the needle seat swells and pushes it down lower so it doesn't fill the bowl up far enough, then it stalls out. While you are in the process of re-starting it, it fills itself back up enough to start again.
You may also have some water in your fuel that could cause an intermittent stumble until it passes through then recovers. 
You could have had water in a fuel container that got into the fuel tank.
Another possible thing is a fuel line swelling shut internally not letting enough fuel through or even a bad spark plug, even a plug wire/ignition coil shorting out intermittently. 
Just a couple things to check.


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## 140278 (Aug 27, 2020)

welcome to the SBF

I'm with ST on the bad vitron needle seat ,


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## James R (Feb 2, 2021)

Thanks for the reply. Fuel line is pretty new as is the shut off valve. If i drop the bowl and then turn that valve back on, the fuel comes out pretty quickly. Gas can is clean and is used regularly on other small engine stuff I have. Fuel is fresh.
I pulled the float last night for inspection. Its brass and looks fine. The needle is good/clean. The seat is fairly new. How do I adjust the height of the float level? Seems to just pivot in there in a fixed position. 
I can't see a fuel supply issue. At times it will run full speed sitting there in the driveway and as soon as I touch the auger lever, it will immediately die. Other times I'll get the auger engaged, it stumbles, then recovers enough for me to make a few partial passes through the snow, and it's throwing the stuff very well, and then a few minutes later it just stalls. When it does, no warning, it just dies. A restart is instant but rough, smoking, smelling rich for about 5-10 seconds, then finally the rpm's come up and it smoothens out again. I don't get it???


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## Mike76 (Nov 21, 2020)

IT really does sound like water in the fuel... I've had similar behavior when that happens. HAve you drained the tank completely, then added fresh fuel? It wouldn't be the fuel in the can that is the problem, but some water in the tank of the blower.


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## 3vanman (Nov 21, 2017)

Start by checking the carb and fuel.
It is also possible the valve lash is out of adjustment (Happens with Tecumsehs), especially those that are 24 or so years old.


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## arienskids (Jan 26, 2018)

60 psi with electric start is borderline, check your valve lash as noted above


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## James R (Feb 2, 2021)

tank was emptied completely as was the carb, then refilled with fresh gas. same issue. I did notice somethin odd though.... that once it is running, if I just put my hand on the governor and try to bump up the rpm a bit, it dies, so maybe the first set of replies about lack of fuel IS the issue. I'm going to yank the carb off completely again and have another look, I may have missed something.


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## Mike76 (Nov 21, 2020)

check the hole on the carb bowl bolt... it is small and can get clogged. That usually causes starting issues but if it's only partilly clogged it might cause other issues.


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## James R (Feb 2, 2021)

Yanked it for the 3rd time, pulled the viton seat and blew it out again...... and son of a %*&#$!..... Found a very tiny piece of debris lodged in the entry way upstream above it. I had sprayed cleaner in there and blew through it with compressed air prior so i thought it was clean. I guess not. Looked like old fuel line hose, a small piece of black stuff, no bigger that a coarse granule of pepper. Like the size of the hole in the viton seat. got that out, reassemble, it fired right up.
I made 2 full with passes in 20+" of snow (slow speed of course) and it had no issue. The governor kicked in and it made that familiar "under load" sound and just ate right through that stuff. Thanks guys!!!! You save me a ton of money.
Heading back out to finish the driveway and do the old dudes next door so he doesn't have a heart attack shovelling.


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## 3vanman (Nov 21, 2017)

Glad to help. 
When you get it back in warm and toasty, and out of fuel you might consider replacing the fuel line, as most likely it is starting to deteriorate.
Or run it for the winter, and make the fuel line a "warm weather" weekend project.


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## James R (Feb 2, 2021)

Just finished doing 4 driveways. Ran flawlessly under full load.
The fuel line was just replaced recently because the old was was rotted and leaking. Probably got some of it into the carb and it finally got wedged into that seat area. Something so tiny can cause such huge issues.
I think come spring I will check/replace the valves, lap the seats and maybe even give it rings and bearings.


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## Oneacer (Jan 3, 2011)

If its running good, I would not delve into an engine tear down, but that is me .... my motto, ... if it aint broke, dont fix it. 

But hey, some people just enjoy doing that stuff.

Me, I enjoy dis-manteling a machine and re-paint, and put back together,


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## James R (Feb 2, 2021)

I enjoy that sort of stuff. It’s got a lot of hours on it and could probably use a freshen up. Heck, I yank the engine out of my Chevelle every few years just to take it apart, tinker with some of it and put it back together again.


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