# 5 HP Snowking Techemseh



## Toro-8-2-4

My Techumseh is starting to vibrate when at idle and I am not sure what is going on. It may be something internal.

When it is under load it is not bad. 

When at not under load it vibrates so much it causes the Key, located on the heat box, to fall out. I tried to bend the key guide to hold it in firmer and it has been to no avail. After all the key is plastic and it just deforms and finds its way out enough to get the circuit to ground out.

Has any one else had a similar problem???? and if so what was the cause and any solution.

I am ready to jump out that key circuit so I can get the job done with out an interruption every 2 minutes.


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## Shryp

You can unplug one of the wires going to the key. Tecumseh flatheads are known for some vibration. Has it always been this way? You might have some other stuff on your blower that is loose and amplifying the vibration when it rattles too. Also, make sure all 4 bolts holding the engine down are tight and that the base of the tractor is not cracked where the engine is mounted. MTDs are known to get stress cracks on the engine mounting plate.


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## Toro-8-2-4

Thanks for the ideas. 

I removed the belly pan and took a look at everything on the underside. All of the bolts are tight. Motor bolts are tight and no cracks in the tractor base. Nothing looks bad.
I did notice a crack in the heater box near where it bolts to the muffler bracket. This would explain its increased vibration. I did unplug the key grounding wire and ran. It does seem louder and vibrates a bit more but that is about it.

The vibration is enough to cause the gear lever to jump from R1 to R2.

Also noticed the exhaust bolts are loosening. I will get some wavy washer and see if that holds them. I don't want to tighten them too much as I am afraid of stripping the tapped holes in the block.

May be something in the engine. But what?


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## Toro-8-2-4

Just reading this old post and I will update by saying the wavy washers did not work. The heat form the exhaust annealed the washer and it lost its spring effect. It became a plain flat washer. Solved it buy using grade 8, 1/4-20's and heavy duty washers and torqueing down.

I am selling this engine and doing a 6.5 hp Preditor upgrade as Gusto and others have done. the Tecumseh served me pretty well. It always started easily no mater how cold. But 5 hp is not always enough power for a large storm or wet snow. I hope to have smooth snow throwing this coming winter.


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## greatwhitebuffalo

it may have a bad valve that is making it run rough.

or, the ignition is off a bit throwing the timing off, and the engine is either sparking too advanced or too retarded in timing, that would make it rough

point gap affects timing, small gap retards the timing, larger gap advances it, and it's easy to get it on the ragged edge that it still runs but runs rough. that's why a new electronic box ignition is a good idea, it stabilizes the engine spark timing

another issue may be a bent impeller shaft or pulley, or missing vanes on the flywheel throwing it out of balance. these engines are balanced from the factory

carb may be way out of adjustment too


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## GustoGuy

Toro-8-2-4 said:


> Just reading this old post and I will update by saying the wavy washers did not work. The heat form the exhaust annealed the washer and it lost its spring effect. It became a plain flat washer. Solved it buy using grade 8, 1/4-20's and heavy duty washers and torqueing down.
> 
> I am selling this engine and doing a 6.5 hp Preditor upgrade as Gusto and others have done. the Tecumseh served me pretty well. It always started easily no mater how cold. But 5 hp is not always enough power for a large storm or wet snow. I hope to have smooth snow throwing this coming winter.


Do you have a dual shaft 5hp Tecumseh or a single shaft? The single shaft swaps are really easy to do while the dual shaft engines are more complicated since you will have to flip the gear box and have the friction drive wheel move to the other side of the spinning friction disk. I have 2 reverse and 5 forward gears now after I did my conversion. If you hook it up directly you will have 2 towards and 5 reverse and the speed of the blower will also be faster than before. Post a picture of your machines friction drive. Since it is an MTD it should look exactly like mine did.


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## Toro-8-2-4

Greatwhite: Good input. This engine is newer and does not have points. No adjustment on the magneto pick up. it is fixed. I know I do have a loose valve guide on the exhaust. I did grind the valve stem down a few years ago to make up for seat wear. The muffler does get hot suggesting it is not seating well. I know it can be reamed and a new oversized valve installed. Not sure if it is worth it or even if that will 100% solve the vibration. The fly wheel and pulleys are all in good shape. So it probably is the valve or something internal. At the end of the day it is still 5 hp when running at its best.


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## Toro-8-2-4

Hi Gusto:
I have a dual shafts making it more complicated but I feel confidant I can do it with my machine.

I have read most, if not all, of the posts here on this topic.
MY machine is MTD made similar to yours and the others who posted pics.. I think I can do the transmission flip. I know one member only flipped the bracket on the hex shaft and said he had room to leave the gear alone. I am not sure if one installs a larger friction plate/pulley if this will hold true. He also bent the speed selector linkage to clear the friction wheel and avoided having to move the mounting bracket and shim the shaft with washer. 
I was wondering about the pulley diameters that people have found optimum. I know some change the friction disk plate/pulley to a larger one to slow down the drive. Is that worth the investment of $75 dollars (or more)?

I know most ended up with a 2" upper pulley. I recall one member using a 1.75" pulley. Most available in that size(with a .750 bore) are die cast and I know some advise not to use them. What is your experience here?

Did you upgrade the belts to 1/2 wide vs. the 3/8 wide?

Thanks in advance!


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## greatwhitebuffalo

Toro-8-2-4 said:


> Greatwhite: Good input. This engine is newer and does not have points. No adjustment on the magneto pick up. it is fixed. I know I do have a loose valve guide on the exhaust. I did grind the valve stem down a few years ago to make up for seat wear. The muffler does get hot suggesting it is not seating well. I know it can be reamed and a new oversized valve installed. Not sure if it is worth it or even if that will 100% solve the vibration. The fly wheel and pulleys are all in good shape. So it probably is the valve or something internal. At the end of the day it is still 5 hp when running at its best.


 loose valve guide means you're probably leaking there, and it would leak exhaust pressure into the crankcase, and possibly blow into the carb via the blowby tube if so equipped and throw off the fuel metering. the crank pressure would also put positive pressure under the rings and tend to push blowby into the combustion chamber. I'd get the fixed first, add to it the valve may not be sealing and seating. look there.


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## GustoGuy

Toro-8-2-4 said:


> Hi Gusto:
> I have a dual shafts making it more complicated but I feel confidant I can do it with my machine.
> 
> I have read most, if not all, of the posts here on this topic.
> MY machine is MTD made similar to yours and the others who posted pics.. I think I can do the transmission flip. I know one member only flipped the bracket on the hex shaft and said he had room to leave the gear alone. I am not sure if one installs a larger friction plate/pulley if this will hold true. He also bent the speed selector linkage to clear the friction wheel and avoided having to move the mounting bracket and shim the shaft with washer.
> I was wondering about the pulley diameters that people have found optimum. I know some change the friction disk plate/pulley to a larger one to slow down the drive. Is that worth the investment of $75 dollars (or more)?
> 
> I know most ended up with a 2" upper pulley. I recall one member using a 1.75" pulley. Most available in that size(with a .750 bore) are die cast and I know some advise not to use them. What is your experience here?
> 
> Did you upgrade the belts to 1/2 wide vs. the 3/8 wide?
> 
> Thanks in advance!



I used a 2 inch steel pulley for the drive and a 3 inch steel pulley for the auger. Do not use the fractional die cast zinc pulleys they are not made to stand up to the power of a small gasoline engine. Yes, installing a larger bottom friction disk pulley will slow down the speed of the snowblower and give you more useful blowing speeds. With the original 6 inch bottom pulley it was much faster than with the new 8.5 inch bottom pulley. It is just a bit faster than when it had the Tecumseh but the results speak for it self with the more powerful engine


Mtd Yardmachine 5/22 repower with Harbor Freight ...


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## Toro-8-2-4

Gusto. Nice video. That looks like about 10 inches of snow.

In the video what position was the speed selector on?... And was the lower pulley the OEM or did you have the larger pulley installed at that time?

I found a cast iron 1.75" diameter pulley but it is for a 1/2" wide belt. This will slow it down another 12.5%. I am not sure if the lower pulley will accept the 1/2" belt.


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## GustoGuy

Toro-8-2-4 said:


> Gusto. Nice video. That looks like about 10 inches of snow.
> 
> In the video what position was the speed selector on?... And was the lower pulley the OEM or did you have the larger pulley installed at that time?
> 
> I found a cast iron 1.75" diameter pulley but it is for a 1/2" wide belt. This will slow it down another 12.5%. I am not sure if the lower pulley will accept the 1/2" belt.


About 11 inches of snow. I like that the snow flys 40 feet now all the way into the other yard

Lowest speed. 5th is a pretty fast walk with the Predator 212cc. I bought a larger pulley. But it is 1/4 inch wide belt friction disk and the power of the Predator chews it up with in 1 season. I will be replacing it with a 3/8th inch belt lower pulley friction plate before the snow flys. I feel that it will handle the output of the Predator engine better than the thinner belt and I will get more life out of it.


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## Toro-8-2-4

Got it. The 8.5" pulley friction plate that was described in one of the earlier posts was MTD P/N 65604025A. Is this the plate that took a 1/4" wide belt that you will be replacing? If so, can you share the P/N of the replacement that can accept the 3/8" wide belt.

Thanks.


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## GustoGuy

Toro-8-2-4 said:


> Got it. The 8.5" pulley friction plate that was described in one of the earlier posts was MTD P/N 65604025A. Is this the plate that took a 1/4" wide belt that you will be replacing? If so, can you share the P/N of the replacement that can accept the 3/8" wide belt.
> 
> Thanks.


 I seen this one on ebay can take a 3/8 inch wide belt which will be stiffer and should be much less likely to break down like the 1/4 inch belt


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## Toro-8-2-4

Good find Gusto!
Just a thought.....
Are you sure the shaft size is compatible. Just from scaling off the photo I am guessing it is 5/8. Also has a flat on it.


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## Grunt

Toro-8-2-4 said:


> Good find Gusto!
> Just a thought.....
> Are you sure the shaft size is compatible. Just from scaling off the photo I am guessing it is 5/8. Also has a flat on it.


I don't think this is the correct picture. Looks like, and is described as, friction drive disc, not a pulley.


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## GustoGuy

Toro-8-2-4 said:


> Good find Gusto!
> Just a thought.....
> Are you sure the shaft size is compatible. Just from scaling off the photo I am guessing it is 5/8. Also has a flat on it.


There is a v-belt groove that runs along the outside perimeter of the friction disk. You just can't see it in the picture. Other views of the friction disk shows the v-belt groove


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## Toro-8-2-4

I understand that there is a v belt groove on the out side diameter.
Here is another view.

Snowblower friction disc | 656-04055 | SearsPartsDirect


I am wondering if the shaft that is pressed in to the bearing will be a drop in installation with most MTD's It mounts into the pivot plate. I need to refresh my memory as to how it connects on my machine. It is another consideration to be aware of. Still .....a good find!


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## Grunt

GustoGuy said:


> There is a v-belt groove that runs along the outside perimeter of the friction disk. You just can't see it in the picture. Other views of the friction disk shows the v-belt groove


I apologize for my ignorance of the part described.


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