Stihl 066 Clutch Problem

[WoodTick007]

My brother and I were cutting some very large Elm today....He was using his 066 with a 36 inch bar. During a cut the clutch loosened up and would not drive the chain..... It was crazy:crazy1: :crazy1: I have never see this happen before.

What would/could cause the clutch to come off? How can this be avoided in the future?

 

[Lakeside53]

The clutch? or just the drum?

The drum is held on my a circlip. If that clip is stretched or bent it will break or just come off, then the drum can exit..... The clip has to be removed before the clutch can come off..


If the end of the crank is damaged, the clip can come off anyhow..

If the clutch has come off, that means it was never torqued down correctly in the frist place. I do not agree with the often stated wisdom of "just put on and slam on the brake a few times.." there is a reason for applying the correct torque, particularly on the larger saws.

 

[WoodTick007]

How may inch/pounds should the clutch be torqued down to?

 

[Lakeside53]

33 FOOT/lbs...

or 396 inch/lbs..

Use a 3/8 rope coil instead of a piston stop. Make sure your piston is above the exhaust port AND the decomp valve is UP...

 

[drunkenredneck]

Are you sure that the clutch actually did come off. I have a hard time seeing this as the clutch on it is reverse thread. So my thinking would be the more you ran the saw the tighter the clutch would get???

 

[Lakeside53]

Unfortunately if it's not tight enough to start with, the clutch spins off when the saw decelerates faster than the clutch... Trust me... I had to find a lot of parts all up my driveway...

 

[drunkenredneck]

Ok that makes sense now that I think about it Lakeside.