Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I've got a 28"/8.5hp/2-stage Yardman (MTD) snow thrower and it looks like the 20-tooth worm gear that transfers power from the worm/impeller drive shaft to the augers is shot (worm drive shaft from the impeller turns but the augers don't). Also wondering why the shear pins, didn't shear but they're fine and the augers are loose on their drive shaft. Didn't check the torque...that may be the problem.

Has anyone out there replaced this gear? If so, I really appreciate benefiting from your experience by hearing the steps you took. At first I thought I could simply pull the auger assembly by punching out the two roll pins that hold the impeller to the shaft but after getting them out it looks like the worm/impeller drive shaft runs through the auger/impeller housing, a ball bearing and  the two auger pulleys. It's a very crowded area around the auger pulleys and this looks like it will turn into a major tear down. I'm pretty handy but beginning to wonder if I should bag it and head to the shop. If they had just put removable side panels on the auger housing, you could easily pull the gear box apart.

All advice appreciated with thanks!

Bill Curry
Snowbound in Walpole, NH!

Thanks much for the suggestions.  If all else fails, I might cut them off by slicing length-wise.  I know someone who is very proficient with an arc welder who can weld the auger back up for me if I need to resort to the slice method.  My Crafsman didn't have grease fitings.  I think I'm going to drill/tap the augers to add some to avoid this problem in the future.  At least we are near the end of the winter so I have time to "play" with this.  JAB