Oil Pump: Testing and Inspection

RELIEF VALVE
Coat the valve with engine oil and check that it falls smoothly into the valve hole under its own weight.
- If it doesn't, replace the relief valve.
- If necessary, replace the oil pump assembly.





DRIVE AND DRIVEN ROTORS
1. Place drive and driven rotors into oil pump body The marks on the rotors must face up.





2. Using a feeler gauge inspect rotor tip clearance, measure the clearance between the drive and driven rotors.
- Standard tip clearance: 0.060-0.240 mm (0.0024-0.0094 inch).
- Maximum tip clearance: 0.300 mm (0.0118 inch).
- If the tip clearance is greater than maximum, replace the rotors as a set.





3. Using a feeler gauge, inspect rotor body clearance, measure the clearance between the driven rotor and pump body.
- Standard body clearance: 0.100-0.175 mm (0.0039-0.0069 inch).
- Maximum body clearance: 0.200 mm (0.0079 inch).
- If the body clearance is greater than maximum, replace the rotors as a set.
- If necessary, replace the oil pump assembly.





4. Using a feeler gauge and precision straight edge, inspect rotor side clearance, measure the clearance between the rotors and precision straight edge.
- Standard side clearance: 0.030-0.090 mm (0.0012-0.0035 inch).
- Maximum side clearance: 0.120 mm (0.0047 inch).
- If the side clearance is greater than maximum, replace the rotors as a set.
- If necessary, replace the oil pump assembly.
5. Remove drive and driven rotors.