PISTON RINGS 0.50 YAMAHA 64D-11603-02

Function and technical context

The piston ring is an essential component of the engine's internal sealing system that works in the combustion chamber. Its function is to create an airtight seal between the piston and the cylinder walls, preventing combustion gases from escaping into the crankcase and allowing the pressure generated in the explosion to be effectively transmitted to the crankshaft. The +0.50 mm oversize indicates that this part is designed for cylinders that have been ground to this specification, ensuring the precise fit necessary to maintain engine compression. A worn or damaged ring causes loss of compression, increased fuel consumption, blue smoke in the exhaust and a significant reduction in available power.

When to replace this part?

Piston ring wear typically manifests itself with gradual loss of compression in one or more cylinders, persistent smoke in the exhaust even in normal operation, and irregular engine behavior that progressively worsens. These components must be checked during major engine maintenance or when cylinder grinding is performed, and it is advisable to replace them preventively during this intervention to avoid future compression leaks and secondary damage to the cylinder walls. Replacement in a preventive phase avoids unexpected engine shutdowns while sailing and significantly prolongs the useful life of the piston-cylinder assembly.

Equivalent manufacturer part numbers