# 726 final drive sprocket groove pin?



## amuller (Jan 3, 2016)

The only consistent problem I have with this old machine is with the way the final drive sprocket is pinned to the shaft. It is supposed to be a solid 1/4" "groove pin" but that had sheared. (Probably why I was given the machine....)

I have been using grade 8 1/4" bolts, but these only last a few hours before shearing. I've been assuming these are at least as strong as a groove pin but maybe I'm wrong about that. I've been thinking about drilling out the shaft and sprocket for a 5/16" or 3/8" pin or bolt but that would be a bit of a pain.

Suggestions? Is this a common problem with these machines?

Thanks.


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