Snow Blower Engine Swap / Belt Sizing Help

[Bill D 2,218]

I am swapping a 12 HP Tecumseh onto a Toro Powermax 828 LXE snowblower and I ran into a problem I didn't expect.  The crankshaft on the 12 HP is 1/2" higher than the 8 HP it's replacing.  The stock auger belt is a 43" x 1/2" belt, and the stock drive belt is a 35" x 3/8" belt.  I'm thinking I need a to buy a 43.5" belt and  a 35.5" belt.  Am I right?   Is there a calculator for belt sizing that I could use?

 

Also, what is the best source for high quality belts in half sizes for this type of application?  It would be great if I could just go to TSC or NAPA and get a 36" and 44" belt.  Thanks for the help.  Bill  

[squonk 43,361]

Half inch sizes are hard to come by. Most power equipment belts are whole inch sizes and most places only stock 1/2" and 5/8" widths. I would go to a Napa and get a 4L440W and probably have to order a 3L 360W belt. 

 

To get half inch sizes you will probably have to go with an automotive engine belt

 

Napa # 25-7350 is a 3/8" X 35 5/8" belt

 

# 25-9430 is a 1/2" X  43 3/8" belt

[ri702bill 9,202]

@Bill D, @squonk If you find you need a belt in a 1/2" odd-size size, check McMaster-Carr - they MAY  have what you need. Be sure of the size, though ....

[squonk 43,361]

McMaster sells Gates. I have a Napa belt size catalog and Napa belts are Gates There are some special length belts but not many.

[wallfish 17,849]

Or, use spacers to raise the engine up a little and use the belts you can find

[Bill D 2,218]

2 hours ago, wallfish said:

Or, use spacers to raise the engine up a little and use the belts you can find

I can't raise it anymore or the belt covers won't fit.

[Pullstart 65,795]

Remember that if the engine moves 1/2”, that’s 1/2” up travel and 1/2” down travel… so another inch larger approximately.

[Bill D 2,218]

4 hours ago, Pullstart said:

Remember that if the engine moves 1/2”, that’s 1/2” up travel and 1/2” down travel… so another inch larger approximately.

That's kinda what I was thinking too.

[Handy Don 13,683]

14 hours ago, Pullstart said:

Remember that if the engine moves 1/2”, that’s 1/2” up travel and 1/2” down travel… so another inch larger approximately.

Only if the engine is moving directly away from the trans. Upward is at an angle to the trans input pulley so the effect is smaller.

 

On 8/18/2022 at 9:12 PM, Bill D said:

I can't raise it anymore or the belt covers won't fit.

I like your thinking here. 

[Pullstart 65,795]

17 minutes ago, Handy Don said:

Only if the engine is moving directly away from the trans. Upward is at an angle to the trans input pulley so the effect is smaller.

Right.  I imagine the transmission apparatus is below the engine on this one.    

 

 

[Bill D 2,218]

Tried a 44" belt on the auger and it fit like a glove.  36" should work for the drive belt.  @Pullstart.  Kevin you were spot on with your earlier comment.