Oil Pump: Testing and Inspection

1. Check the inner-to-outer rotor radial clearance on the pump rotor. If the inner-to-outer rotor clearance exceeds the service limit, replace the inner and outer rotors.
- Inner Rotor-to-Outer Rotor Radial Clearance:
- Standard (New): 0.02-0.14 mm (0.001-0.006 inch)
- Service Limit: 0.20 mm (0.008 inch)





2. Check the housing-to-rotor axial clearance on the pump rotor. If the housing-to-rotor axial clearance exceeds the service limit, replace the set of inner and outer rotors and/or the pump housing.
- Housing-to-Rotor Axial Clearance:
- Standard (New): 0.03-0.08 mm (0.001-0.003 inch)
- Service Limit: 0.15 mm (0.006 inch)





3. Check the housing-to-outer rotor radial clearance. If the housing-to-outer rotor radial clearance exceeds the service limit, replace the set of inner and outer rotors and/or the pump housing.
- Housing-to-Outer Rotor Radial Clearance:
- Standard (New): 0.10-0.18 mm (0.004-0.007 inch)
- Service Limit: 0.20 mm (0.008 inch)
4. Inspect both rotors and the pump housing for scoring or other damage. Replace parts if necessary.