40mm Piston Kit Fits Jonsered 2041 503489001

A 40mm piston kit for the Jonsered 2041 chainsaw. It replaces 503489001, since superseded to 503489002. A scored piston is usually a lean condition, so pressure and vacuum test the crankcase and fix any air leak or fuel fault before the new piston goes in. Check the cylinder for scoring and aluminum transfer, use a ring compressor, fit the circlips fully and check the carburetor tune.

• 40MM PISTON KIT - Piston, rings, wrist pin and circlips.
• FITS JONSERED 2041 - The 40mm saw. Check the model on the starter cover before ordering.
• REPLACES 503489001 - Since superseded to 503489002, so either number gets you here.
• FIND THE CAUSE FIRST - A scored piston is usually a lean condition: an air leak at the intake or crank seals, or a fuel fault. Pressure and vacuum test the crankcase before the new piston goes in.
• INSTALLATION - Check the cylinder for scoring and aluminum transfer, use a ring compressor, fit the circlips fully with the gaps away from the notch, and check the carburetor tune before working it hard.