PISTON RING GAME 0.50

Function and technical context

The piston rings are the sealing elements responsible for maintaining compression within the cylinder, preventing combustion gases from escaping into the crankcase and preventing lubricating oil from rising to the combustion chamber. They work in the compression and lubrication system of the marine diesel engine, lodging in the grooves of the piston and resting against the inner wall of the cylinder liner. This +0.50 mm oversize clearance is specifically used when the cylinder has been subjected to a grinding process, thus restoring the correct working clearances between the piston and the liner and recovering the factory compression values. Without rings in good condition, the engine progressively loses power, oil consumption increases and bluish smoke emissions are produced, characteristic of the oil that burns in the chamber.

When to replace this part?

The need to renew the piston rings is detected by symptoms such as a notable loss of compression in one or more cylinders, excessive consumption of lubricating oil, appearance of bluish smoke from the exhaust, or presence of gases in the crankcase (blow-by). These components are checked or replaced as part of a major engine overhaul, generally associated with cylinder resurfacing or when compression measurement shows values ​​below the specified limits. Addressing the replacement at the time of grinding, using the correct oversize, is the way to guarantee that the engine repair is complete and lasting, avoiding having to disassemble the assembly again due to saving parts that in the end is counterproductive.

Equivalent manufacturer part numbers