Customer said his clutch was slipping on his STIHL 021

[lurk]

Customer said his clutch was slipping on his STIHL 021 Chainsaw. Usual questions asked at the counter, is it running ok, are you giving it enough revs, chain sharp etc. and it was booked in for a diagnosis.

In the workshop: Engine was up to speed and sounded good, actually smoother and quieter than most, and it looked in good condition. So we had to dig deeper.

It wasn't until we tried to remove the clutch that we discovered the reason.

https://youtube.com/shorts/37ueS686IqI?si=HYjeSg78rIjakotK

[Don P]

I've heard of that but never seen it. How did it happen?

[lurk]

Don, I really don't know why it happened. Maybe a flaw in the steel, combined with a snag of the chain. I really don't know.

You can see it snapped just inside the bearing hence why it ran and sounded fine.