6.7L Cummins Rocker Levers – Crankcase Breather (Internal) – General Information

Depending on the application, two different breather systems are used.
โ€ข An internal system, which is a part of the rocker lever cover assembly.
โ€ข An external system, which mounts at the rear of the engine above the flywheel housing.
Both systems are closed crankcase breather systems, meaning the crankcase gases are vented into the intake
system at the inlet to the turbocharger.