It is mounted in the lower section/seal area of the cylinder liner, between the liner and the engine block. It is part of the cylinder liner sealing system. Its main function is to seal the cylinder liner against the engine block, prevent coolant from flowing into unintended areas, prevent contamination between coolant and engine oil, and maintain proper sealing of the cylinder liner during the engine’s thermal cycles.
Verified compatible Cummins engines: 6C 8.3, 6CT 8.3, 6CTA 8.3, ISC 8.3, QSC 8.3, ISL 8.9/9, QSL 8.9/9.
I recommend verifying compatibility using the ESN (Engine Serial Number), CPL, QuickServe/Cummins Catalog, cylinder liner number, block number/casting number, engine year/configuration, and a dimensional comparison of the ring.