So I've got an older Craftsman 536.881230 Snowblower. It's a 12.5HP Tecumseh motor. Been having trouble with the auger belt/pulleys.





A couple weeks ago I was snowblowing and all of a sudden the auger stopped spinning. I took the cover over, and the belt was a little loose and had seen better days. Both of them. So I bought new parts, and installed them, and after about half the driveway the auger stopped working again. I tore it apart again to find the keyway on the pulley for the auger belt had sheared.



Now, it's a 12.5Hp unit with a 33" clearing path. It should be able to handle a noreaster, and I was crawling through about 3/4 inches of snow. I've got a backup 5hp TroyBuilt that'll clear 4 inches.



What in the world could have put enough force on the pulley to shear the keyway? Even if a belt if overtight, it should wreck or snap a belt before a hardened keyway. I tried welding another keyway back onto the pulley (storm coming this weekend) and it immediately sheared off, in probably 15 feet of blowing. Now admittedly I'm not a welder, and it was just a couple tac welds. I have checked the pulley with a micrometer, it's still round (not egg shaped from the pulley).



Everything seems to spin fine by hand. I'm going to head to sears and see if replacement pulleys are available.


What else could be causing this? Everything spins fine by hand....