Piston Ring Failure – Causes and Prevention


Mechanics and engine technicians often complaint about the premature wearing out of piston rings in heavy duty tractors. This is one of the most common complaints and often the complainants blame the manufacturers for low quality or defected product. Specific manufacturers are often blamed. However the complaint comes from man OEM companies as well.

Many customers ask for specific rings like ‘original caterpillar piston rings’ without realizing the rings presented to him are also from the same brand. More often than not, it is not the fault of any specific ring but the customer’s conception of economic benefit by changing only the piston ring and ignoring the other associated parts- the piston pin, piston pin retainer, and the cylinder lines. These parts are ignored and used beyond their category and this majorly contributes to piston ring failure. Slight, permanent vibrations are caused in the engine due to the normal wear on these metal parts. Premature wear is caused to all parts because of this vibration as well as on the ring of the piston head.

A 2800 rpm rating engine when at high speed can have minor vibrations which cause additional stress and strain on internal engine components. Damage is caused to the used cylinder liner with microscopic indentations and scratches are worn out. Because of all this the surface becomes uneven on which the piston rings have to move up and down at 2800 rpm.

This is what majorly contributes to the failure of piston rings. Rings from original companies like Caterpillar and Cummins will permanently fail in this situation. This shows that the problem does not lie with the piston rings, but actually the reused cylinder liners.

This is why a warranty for rings is provided by OEM and aftermarket companies only if along with the rings, the other internal components- the cylinder liner, piston pin and piston pin retainer are changed.

Therefore it is always recommended to get the whole liner kit changed at a tie rather than just the piston rings as the whole system is made up of a complex network. Despite the fact that it is a little more expensive, in the long run, it is beneficial in a number of ways. The engine performs better; less possibility of break down, fuel consumption is lowered, lesser pollution and GHG emissions. It saves one from frequent visits to the mechanics for piston rings and provides peace of mind.

D.S.S. was founded in 1983 to serve the high performance auto and Racing industry. They sell parts from all quality manufacturers like AEM, Clevite, Edelbrock, Ford racing Performance parts, Lunati Manley performance, World products and many more.