How to Repair the Drive Sprocket of a Chain Saw

Set the chain saw, switched off and cooled, onto a workbench. Pull the hand brake backward to release the brake, allowing the chain to spin freely. Loosen and remove both bar nuts on the right side of the chain saw using the combination bar tool’s wrench end.

Lift the bar cover, bar and chain off the chain saw’s engine. Wedge the tip of the screwdriver side of the bar tool underneath the C-clip, holding the clutch parts to the crankshaft. Pop this C-clip off the crankshaft.

Slide off the washer, needle bearing, drive sprocket and clutch drum from the crankshaft. Separate these parts from one another. Wipe off the crankshaft stub with a rag.

Lubricate the needle drive bearing, coating the outer bearings with a thin layer of all-purpose engine grease. Insert the needle drive bearing into the replacement sprocket.

Set down the clutch drum, needle drive bearing with sprocket and washer onto the crankshaft stub. Fit a new C-clip around the end of the crankshaft stub. Reattach the chain, bar and bar cover.