# 3" pulley upgrade



## cadmobile500

hi. my name is tom and ive been lurking on this forum for a couple years now.
I have a mtd 31be665e118 snow blower 10/24". it was originally powered by a 10hp Tecumseh engine but that seized at the end of last season. I repowered it with an 8hp Tecumseh since it was the only engine I could find/afford at the time that would fit. this snow blower requires a dual shaft engine.

anyways, I added an impeller kit and bought a mini tach and turned the governor up from 3300rpm to 3600rpm. it does pretty well and will eat 4" of dry snow on speed 5 without bogging down. itll handle pretty much everything else we got this year on speed 3.

I wanted to increase the impeller speed by increasing the the pulley size on the engine. this blower has dual auger pulleys. actually the upper pulleys are 
pulley halfs and are listed at 2.6" diameter and the auger pulleys are listed as 8".

what im wondering is are the numbers used to describe the pulleys the pitch size or pulleys o.d. I didn't want to order a pulley just based on its o.d. the 3" pulleys I saw online had a 2.2" pitch diameter with an "A" belt.

based on the descriptive sizes of my pulleys my impeller speed should be 1170rpm. how do I figure out the pitch of the current pulleys?

has anyone already figured this out?

I think my next purchase is going to be one of those reflective tape tach;s

thanks in advance. tom


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## motorhead64

Hi cadmobile
Hope this doesn't make you dizzy...it did me. MH
Notes on Pulleys and Belts


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## MrDman

Hi Cadmobile,
When you install a larger pulley on the motor it will make the auger faster but

you lose torque.It may start to pull the motor down.

You can try it if it doesn't work your just out a pulley and a new belt.

Tom


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## cadmobile500

we had 10" of dry fluffy snow last night. I had no problem clearing the driveway today in 3rd gear but had some snow spilling out the cleared side taking 3/4 width cuts. I was thinking a little more auger/impeller speed would help with through-put. I cant stand running the snowblower any slower than 3rd gear. makes me walk like an old lady-lol. minimal bogging in the deep drifts. bet the rpms never dropped below 3400rpm.


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## brassmonkey

motorhead64 said:


> Hi cadmobile
> Hope this doesn't make you dizzy...it did me. MH
> Notes on Pulleys and Belts


Fascinating although made me dizzy indeed! :smiley-confused009:

Make your own pulleys? That's right up there with make your own spark plugs and tires! :wacko:


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## Shryp

brassmonkey said:


> Make your own pulleys? That's right up there with make your own spark plugs and tires! :wacko:


Skip to 19:12


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## 43128

Shryp said:


> Skip to 19:12
> 
> https://www.youtube.com/watch?v=vAf2ZpILjeY


lol from the same guy that got an f150 for 200 bucks!


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## jtclays

Here's a really basic "what will this change do" type calculator. It will also get you in the ball park for belt length, so if you have a 36" brand new belt sitting around, plug in your measurements and find your auger mod comes out to 36" exactly, you know you need bigger because you have to factor in idler run in and not engaged free run for brake to work. Beats trying to loop your wife's sewing ruler around the pulleys and then explaining why it's got grease on it:facepalm_zpsdj194qh (along the same explanation path of answers to: where is the baster?, where is the hair dryer?, why are the oven mitts in the garage?, who is using all the Pam spray, do these cans leak?, and why is the dog's nose orange? (specific to Ariens and Allis repainters)).:wavetowel2:
Pulley Calculator. RPM, Belt Length, Speed, Animated Diagrams


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## YSHSfan

jtclays said:


> Beats trying to loop your wife's sewing ruler around the pulleys and then explaining why it's got grease on it:facepalm_zpsdj194qh (along the same explanation path of answers to: where is the baster?, where is the hair dryer?, why are the oven mitts in the garage?, who is using all the Pam spray, do these cans leak?, and why is the dog's nose orange? (specific to Ariens and Allis repainters).:wavetowel2:


:signlol::signlol::signlol:


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## NMLHoldingsLLC

Hi Cad
I'm here in NH also (Manchester)
Did you get the upgrade completed?
How are the results?

I'm looking to do something similar on my Ariens 1336 Pro.
Runs good, just can't move snow through the impeller and out like my other Ariens 926 LE with a dual belt kit
Both have the impeller kit upgrades

Thanks


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## 1132le

NMLHoldingsLLC said:


> Hi Cad
> I'm here in NH also (Manchester)
> Did you get the upgrade completed?
> How are the results?
> 
> I'm looking to do something similar on my Ariens 1336 Pro.
> Runs good, just can't move snow through the impeller and out like my other Ariens 926 LE with a dual belt kit
> Both have the impeller kit upgrades
> 
> Thanks


Its almost a 4 yr old thread dont think you will get a response
a 1336 pro should blows the doors off a 926 

fix whats wrong with the 1336 pro


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## Oneacer

4 year old post … pretty good bet OP moved on … just sayin …


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