Piston Ring Scratches And Breaks

2025-05-09 14:30

Piston ring scratches and edge breaks is rare to see especially after very short run, some of the scratch or breaks can feel with a fingernail, or only can be seen from magnifier, which may not be easily catch or observed from other aspects like smoke, oil consumption, loss of engine power, maybe only be found by early regular endoscope check of liner, which definitely required further inspection and potentially repair or replacement.

Root cause of above mentioned failure, especially for engine runs only less than 100 hours.

●Assembly issue:

The ring been twisted or broken during installing, or improperly handled (like filed or dropped in hard surfaces), or the cleanliness of the assembly process can’t be guaranteed.

●Ring manufacturing issue:

Ring gas is too small.

Ring edge not been deburred.

Small / tiny crack left in ring due to ring manufacturing or handling / transportation process.

●Foreign Material:

Metal or debris entering the engine through the air filter system.

Sand or metal dropped from air system (including turbochargers), such as lack of shot blasting process, sand inclusion dropped from air system during engine running.

●Engine Overheating:

High temperatures can cause the piston / ring to expand excessively, leading to scuffing and damage.

●Combustion Failure:

Problems with the fuel injection or ignition system can lead to incomplete combustion and damage to the piston and rings.

●Piston Ring Fracture:

Pistons can break due to forced or fatigue fractures, often caused by foreign bodies colliding with the piston.

●Insufficient lubrication or improper lubricant:

Low oil level, malfunction lubrication system, or degreed lubricant can lead to insufficient lubrication between ring and liner.

●Too much carbon deposit:

Carbon deposit can lead to insufficient ring clearance, which lead to over expansion of ring, finally break the ring edge and makes ring scratched.

In summary, if you notice scratches or breaks on piston rings, it's crucial to have them inspected, better to have them be replaced, reduce the risk of further damage of other components like piston, liner, air system especially valve and turbocharger.