Repair Guide for a Stihl Chainsaw

Move the safety brake handle backward to disengage the safety mechanism. Slide the choke lever into the closed position. Loosen both bar nuts with the wrench end of the combination bar tool. Loosen the bar tensioner screw counterclockwise until it stops.

Hold the bar cover, bar and chain. Disconnect the chain from the bar. Clean all three of them with a brush and rag, inspecting them for damage. Replace any broken covers, damaged bars and worn out chains. Blow out the two oiler holes and the two slots on the guide bar with compressed air.

Unscrew the oiler plate cover, just to the right of the bar posts. Clean the entire area around the clutch, the bar posts and underneath the oiler plate with the brush and rag. Pop the circlip off the crankshaft stub with the tip of the screwdriver end of the combination bar tool.

Slide the washer, sprocket, needle cage bearing and clutch drum off the crankshaft. Clean these parts with the brush and rag while inspecting them for damage. Replace any worn-out or broken parts.

Unhinge the lead wire's rubber boot from the tip of the spark plug. Unscrew the spark plug with the socket end of the combination bar tool. Pull out the plug and, if the tip is dirty, corroded or poorly gapped, replace the spark plug.

Insert the piston stopper into the cylinder hole. Rotate the crankshaft by hand until it hits the piston stopper and can't move. Unscrew the clutch hub with the clutch removal tool counterclockwise for its reverse thread. Pull the clutch assembly and washer off the crankshaft. Clean and replace worn-out shoes and over-stretched springs. Reinstall all other parts in reverse order.