Oil Separator: Service and Repair

Crankcase Vent Oil Separator - 6.7L Diesel

Early build engines









Late build engines









Removal and Installation

All engines

1. Release the fuel system pressure. For additional information, refer to Fuel System - General Information - Gasoline and Diesel Fuel System Pressure Release.

Early build engines

2. Disconnect the crankcase vent oil separator outlet hose from the crankcase vent oil separator.

Late build engines

3. Loosen the clamp and disconnect the Charge Air Cooler (CAC) inlet tube from the CAC and position aside.
- To install, tighten to 9 Nm (80 lb-in).





4. Disconnect the crankcase vent oil separator outlet tube sensor electrical connector.

5. NOTICE: Do not disconnect the crankcase vent oil separator outlet tube from the crankcase vent oil separator, it only can be disconnected from the intake manifold. Removal of the crankcase vent oil separator outlet tube from the crankcase vent oil separator will damage the crankcase vent oil separator outlet tube. A new crankcase vent oil separator outlet tube must be installed.

Disconnect the crankcase vent oil separator outlet hose from the intake manifold by turning the release ring counterclockwise.

- If the crankcase vent oil separator outlet hose needs replacement, cut the lock collar off the crankcase vent oil separator outlet hose at the crankcase vent oil separator and remove.

All engines

6. Disconnect the inlet and outlet fuel filter quick connect couplings. For additional information, refer to Fuel System - General Information - Gasoline and Diesel Quick Connect Coupling.

7. Remove the 2 bolts from the LH fuel supply tube and position aside.
- To install, tighten to 10 Nm (89 lb-in).

8. Detach the vacuum tube retainer from the fuel filter bracket stud bolt.

9. Remove the 3 bolts, stud bolt and the fuel filter and bracket assembly.
- To install, tighten to 10 Nm (89 lb-in).

10. Remove the wiring harness retainer from the crankcase vent oil separator stud bolt.

11. NOTE: Place a shop towel under the oil separator to catch any oil that may leak when removed.

Remove the 3 bolts, stud bolt and the crankcase vent oil separator.

- Discard the O-ring seal and gasket.

- To install, tighten to 10 Nm (89 lb-in).

12. NOTE: Do not lubricate the O-ring seal or gasket prior to installation.

To install, reverse the removal procedure.

- Install a new O-ring seal and gasket.