# Can't figure it out



## Bigbmn (Feb 11, 2017)

Hi all, need someone's help or at least keep me honest.
I bought a used Murray 22 inch snowblower, maybe 15 years old, with a 5 hp tecumseh hssk50 engine, that dies under load. Seems to run fine, but in deep snow stalls, which is what I want it for, it bogs down and will stall. I have done the following:
Replaced gas and the carb with a non oem carb. Fixed valve lash at .004 inches for both intake and exhaust. I did not lap the valves. I also , cleaned head and replaced head gasket, and torqued to specs, 200 inch lbs. Compression is 80 psi. Key is not sheared, what am I missing?


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## UNDERTAKER (Dec 30, 2013)

Bigbmn said:


> Hi all, need someone's help or at least keep me honest.
> I bought a used Murray 22 inch snowblower, maybe 15 years old, with a 5 hp tecumseh hssk50 engine, that dies under load. Seems to run fine, but in deep snow stalls, which is what I want it for, it bogs down and will stall. I have done the following:
> Replaced gas and the carb with a non oem carb. Fixed valve lash at .004 inches for both intake and exhaust. I did not lap the valves. I also , cleaned head and replaced head gasket, and torqued to specs, 200 inch lbs. Compression is 80 psi. Key is not sheared, what am I missing?


 That machine is not really suited for anything over 4-5 inches of snow. I know this from past dealing with it a very long time ago. so if your bank roll can do it. be honest with yourself and find something bigger and better, anyhoo ALOHA from the Paradise City.:smiley-rpg027::smiley-rpg027::smiley-rpg027::smiley-rpg027::smiley-rpg027::smiley-rpg027:


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## Kiss4aFrog (Nov 3, 2013)

:welcome: to SBF Bigbmn

How much snow are you talking about and is it fluffy or packed like from a snow plow and what speed are you running the machine into it in ??


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## Bigbmn (Feb 11, 2017)

I'm not yet sure what rpm the machine is running at, and purchased an inexpensive laser rpm meter to check. The snow I was trying to clear was 8 to 10 inches of snow plow snow. Just didn't think the machine should bog down like that


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## 524SWE (Jan 20, 2017)

Bigbmn said:


> I'm not yet sure what rpm the machine is running at, and purchased an inexpensive laser rpm meter to check. The snow I was trying to clear was 8 to 10 inches of snow plow snow. Just didn't think the machine should bog down like that


not the engine speed, the speed (the gear) you're using to drive the machine, my guess is you're not going to be able to use anything above first gear with that small a machine and 8-10" of snow. IMHO slow down and enjoy the blow!


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## drmerdp (Feb 9, 2014)

80psi compression is kind of low. Before you adjusted the valve lash was the engine popping badly out of the exhaust? If so,adjusting valve lash alone might not have been enough and valve lapping might have been required. 

It can't hurt to add some oil to the cylinder through the spark plug hole and recheck compression. Maybe your rings are just really worn, and the engine is plain old tired.


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## Bigbmn (Feb 11, 2017)

I never thought about adding oil and checking compression again. Everything I've read said it was difficult to accurately test compression, since these engines have a compression release to allow easier starting. To me, this machine was big enough for my small property, and I can't imagine it was used that often over its lifetime. Maybe I was expecting too much, and Yes I did have it in a high gear to go through some of the snow faster


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## Kiss4aFrog (Nov 3, 2013)

With an older 5 horse 22" going into the EOD pile about first gear is all you can hope for and you might need to stop a couple times to let it catch up even in first. I know my newer Troy still needs a little help getting through the EOD pile.


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## tpenfield (Feb 24, 2015)

My Toro 521 had the same/similar engine. I found that the fuel mixture had to be a bit on the rich side in order for it to hold up under load. Even then, it needed to go slow through the snow banks, by pulsing the drive lever.

So, I'm not sure how fast you are trying to go through stuff, but maybe it is too fast. 5 HP for a 22" is kind of on the low end. You should be able to go through deep snow (12", etc.), just not in anything more than first gear.

So, I would set the fuel mixture a tad rich and see if the machine can keep up with a slower going.


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## Bigbmn (Feb 11, 2017)

Thanks for all the posts. It was a good project for me, to get this machine to run again. It seems my expectations were too high, thinking thjs two stage would devour snow. I'm all for tweaking as much out of it as possible. This new carb doesn't have any adjustments that I know of. How can I run rich?


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## DuffyJr (Oct 15, 2015)

Kiss4aFrog said:


> With an older 5 horse 22" going into the EOD pile about first gear is all you can hope for and you might need to stop a couple times to let it catch up even in first. I know my newer Troy still needs a little help getting through the EOD pile.


As a long time owner of a 5 horse tecumseh 22" MTD I agree, 99% of the time I can go in 2nd or 3rd gear with the snows we get but 1st gear is need at the EOD and when it gets deep. Just need some patience is all. It's "_The Little Engine That Could"._


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## Dave C (Jan 26, 2015)

Bigbmn said:


> Hi all, need someone's help or at least keep me honest.
> I bought a used Murray 22 inch snowblower, maybe 15 years old, with a 5 hp tecumseh hssk50 engine, that dies under load. Seems to run fine, but in deep snow stalls, which is what I want it for, it bogs down and will stall. I have done the following:
> Replaced gas and the carb with a non oem carb. Fixed valve lash at .004 inches for both intake and exhaust. I did not lap the valves. I also , cleaned head and replaced head gasket, and torqued to specs, 200 inch lbs. Compression is 80 psi. Key is not sheared, what am I missing?


80 psi is low, unless that was with the pull cord. The 5 hp Tec's I've checked are 120-140 psi with the starter. And I think .004" is low clearance. Though the intake usually doesn't change much with age.


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## jtclays (Sep 24, 2010)

I agree with Dave, the .004 is pretty tight, especially for the exhaust, but at least you have some. Usually on the 5hp the exhaust will have little to none when problems arise. Compression readings can be funky with different gauges. Have you looked around the shrouding for any obvious black soot marks? Could just be a head gasket. I know there's a bunch of shrouding, but if you take the front (auger side) and heater box off. You can spray some soapy water around the head to block seam and pull the cord (plug boot removed) to see if you have any bubbles. If it were me, I'd want that exhaust clearance closer to .008 so the head would need to come off anyway.


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## JerryR (Oct 18, 2016)

Bigbmn said:


> Thanks for all the posts. It was a good project for me, to get this machine to run again. It seems my expectations were too high, thinking thjs two stage would devour snow. I'm all for tweaking as much out of it as possible. This new carb doesn't have any adjustments that I know of. How can I run rich?


To enrich it try chocking it a little.
HTH
JerryR


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## Bigbmn (Feb 11, 2017)

Compression was 80 psi with pull chord. I did take off the head and replaced the gasket. The first exhaust valve I ground down too much, so I needed to buy a new one and ground it down for .004 clearance, so I would have room to spare. Spec was .004 to .008 so I thought I'd leave some wiggle room, might ground it down a bit more maybe .006


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## jtclays (Sep 24, 2010)

Did you lap in the new valve? If not, that may be the problem when under load.


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## JayzAuto1 (Jul 25, 2016)

GMorning B/B, I believe the Tecumseh manual lists .010 for the exhaust valve on that engine. Lapping in the valve is critical to ensure proper seating, as you must 'Marry' the new valve face to the old seat surface. Tedious, but quick and essential. And make sure to recheck valve clearance After the lapping process. 

GLuck, Jay


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## Dave C (Jan 26, 2015)

I agree with Jay - I noticed a huge difference in power on mine after adjusting exhaust clearance from 6 to 10. And if not lapped, you can get backfiring.


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## GoBlowSnow (Sep 4, 2015)

You people worry me with the terms you use. 

This is what lapping is. I sure hope you aren't doing this to your valves.


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## Bigbmn (Feb 11, 2017)

I didn't lap it in, but will now.
What manual did you guys see the spec im? The one I found indicate .004 to .008 for both the intake and exhaust


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## JLawrence08648 (Jan 15, 2017)

One of the blowers I have is a 5hp 22" Ariens and I've done 24" and more without a problem, driveway after the town plows is the problem. I've had that blower for 15+ yrs. I've also done deep snow with a 5hp Noma. Now I have a JD 10/32, a Craftsman 10/29, and a 8hp Dynamax (for sale). The 10hp does it faster, I no longer need to use 1st gear!


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## Kiss4aFrog (Nov 3, 2013)

One way to "adjust" a non adjustable carb is to drill the jet. Need to get a set of drill bits that are really small. I got mine on Ebay. This one isn't the particular one I purchased.


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## Dave C (Jan 26, 2015)

Bigbmn said:


> I didn't lap it in, but will now.
> What manual did you guys see the spec in? The one I found indicate .004 to .008 for both the intake and exhaust


The owners' manual for my Craftsman says .010, both valves, which is different than the Tec manual. Dunno why they're different.


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