O-Ring Seal Cummins Engine ISC 8.3 – Engine QSC 8.3
Used primarily in the fuel pump system, at the point where the pump connects to its housing or mounting surface, Cummins officially specifies it primarily for 8.9-liter ISC/ISL Tier 3 engines. It creates a seal between the mating surfaces of the fuel pump system, preventing leaks and maintaining proper circuit integrity. Made of Viton/FKM, 75 durometer, a material resistant to fuels, oils, and high temperatures.
Observed on 6C 8.3, 6CT 8.3, 6CTA 8.3, ISC 8.3, QSC 8.3, ISL 8.9, ISL9 e QSL 8.9 engines.
Before selling or installing an engine, I always recommend verifying the engine’s ESN and CPL, either using Cummins QuickServe or the OEM catalog, or by checking the original number that was removed. The C/ISC/QSC/ISL/QSL family includes numerous revisions to the fuel system, and a cross-reference may only be valid for certain CPLs or configurations.
Conclusion: Part number 5272344 is a genuine Cummins turbocharger oil return pipe/connection, primarily used on 8.9-liter ISC/ISL EPA13 engines. To confirm with 100% certainty that it is the correct part for a specific engine, the ESN (Engine Serial Number) is required.