I am going nuts trying to find a replacement belt that drives the rear wheels for my 
7HP White's Snowblower model number 31AH633E190 serial number 1K169B50456 as taken from sticker on machine, i purchased the machine on Sept. 25 2000. In the manual the belt number is 754-0343.
 
I know that a3L290 belt is a 3/8 belt 29 inches in length.
 
The old belt that was on the machine which was the ORIGINAL BELT is MTD 754-0456, but this seemed to be rather long if I measured the outer circumference and bought another belt based on that measurement, it didn't work!
 
I am NOT a rocket scientist but have a reasonable amount of intelligence, however this has got me stumped!!!

To add to the confusion the factory manual calls for a 754-0343 and the belt that was on the machine was 754-0456.

I'd order the part # that Jacks shows to be correct.
 
You don't know if that belt you currently have is correct or not..
 
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