Making a 451 snow blower work on an 82 series tractor

[mcleveland]

Hello, I'm new here. I wasn't sure exactly where to go with this because it crosses over between IH and MTD models. Anyway, here it goes.

After driving 250 (500 round trip) miles for a 450 snow blower, I found it was a 451. The only difference I can find in these two models are the gear ratio. After attempting to order the 450 gears and shaft, I found that they are no longer available and were quite expensive also. This created plan B - a smaller pulley. With the gear ratio of the 451 being about 2.58:1 and the 450 being about 1.86:1 (0.535) it makes sense to me that I should be able to go from the stock 7 inch pulley to a smaller 5 inch pulley and solve the gear reduction problem. This change, if my calculations are correct, should give me a 40% increase in speed on the input shaft and create a speed which is slightly faster than the 450, simulating a gear ratio of 1.84:1 (0.542).

The only concern that I have thought of and others have also expressed is possible belt slippage due to the smaller pulley. I wasn't overly concerned about this because the PTO pulley on my 782 is smaller than 5 inch to begin with, so any slippage would have been pre-existing on that side.

I just can't figure out why this hasn't been discussed before as this conversion is the easier and cheaper alternative. I have found where people have swapped the gears out, but no mention of anything about pulley diameter.

Any thoughts?

 

[agitch]

This was discussed on another forum just a few days ago. You're right the 451 gear ratio is different to compensate for the pulley size change at the end of the 82 series tractors. You should be fine with changing the pulley size on the blower.

 

[mcleveland]

Finding a 5 inch pulley was easier said than done. I finally managed to track one down that may work. The hub is slightly shorter, causing it to sit 3/8 of an inch closer to the snow gear case. Hopefully it won't cause the belt to jump off or tear the belt up.