Chainsaw

[jamie_patric]

I was going through a branch with my petrol chainsaw and saw the chain had come very slightly loose, as I pulled it from the branch I could see the chain wont spin, engine is running fine but chain will no longer move, any ideas?

[Clanad]

Do you mean even when you accelerate the engine? If so, the clutch assembly, which operates on the centrifugal force principle as failed. It's held together by one or more springs and I suspect one has broken. If not that, the mecanism that attaches the clutch assembly to the sprocket that engages the chain may have sheared.

Take the cover off (usually held on by two bolts through the rear part of the chain guard). You can then inspect the entire mechanism.

Keep in mind that the chain should be slightly loose. For example, on a saw equpped with an eighteen inch chain bar, one should be able lift the chain about 1/2 inch out of it's guide... slightly more if it's hot from running...

[jason.p]

Has the safety lock been engaged?
There should be a bar at the front of the engine casing, push it forward to unlock.

[jamie_patric]

it was the safety lock, thank god for this site i'd of looked silly taking it for repair, thanks for your help!