42mm Piston Kit Fits Dolmar PS-420 Chainsaw

A 42mm piston kit for the Dolmar PS-420 chainsaw, the 42.4cc saw. 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. A scored or worn-through cylinder needs replacing along with the piston. Check the cylinder for scoring and aluminum transfer, use a ring compressor, fit the circlips fully and check the carburetor tune.

• 42MM PISTON KIT - Piston, rings, wrist pin and circlips.
• FITS DOLMAR PS-420 - The 42.4cc saw on a 42mm bore. Check the model on the saw before ordering.
• STANDARD BORE - For the 42mm cylinder. A scored or worn-through cylinder needs replacing along with the piston.
• 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.