Measure the tip clearance of rotors. If the clearance is out of specification, replace the rotors as a set.
Tip clearance:
Specification:
0.04 — 0.14 mm (0.0016 — 0.0055 in)
Measure the clearance between the outer rotor and the oil pump case. If clearance is out of standard, replace the oil pump case.
Case clearance:
Standard:
0.10 — 0.175 mm (0.0039 — 0.0069 in)
Measure the gap between the inner rotor and the oil pump to measure the clearance between the inner rotor and the oil pump cover as shown in the figure. If the clearance is not within the limit, replace the rotor or the oil pump case.
Side clearance:
Standard:
0.02 — 0.07 mm (0.0008 — 0.0028 in)
Check the valve for assembly condition and damage, and the relief valve spring for damage and deterioration.
Replace the parts if defective.
Relief valve spring:
Free length
73.7 mm (2.902 in)
Installed length
54.7 mm (2.154 in)
Load when installed
93.1 N (9.49 kgf, 20.93 lbf)
Check oil pump case for worn shaft holes, clogged oil passages, worn rotor chambers, cracks and other faults.
Check the front oil seal lips for deformation, hardening, wear, etc. and replace if defective.