Remove the plug (A), spring (B) and relief plunger (C).
Coat the plunger with engine oil and check that it falls smoothly into the plunger hole by its own weight.
If necessary, replace timing chain cover.
Inspect the relief valve spring.
Inspect for distortion or breakdown of the relief valve spring.
Inspect the rotor side clearance.
Using a feeler gauge and precision straight edge, measure the clearance between the inner rotors and precision straight edge.
If the side clearance is greater than maximum, replace the rotors as a set.
If necessary, replace the timing chain cover.
Inspect the rotor body clearance.
Using a feeler gauge, measure the clearance between the outer rotor and body.
If the body clearance is greater than maximum, replace the rotors as a set.
Inspect the rotor guide clearance.
Measure the outer diameter of the inner rotor guide.
Measure the inner diameter of the timing chain cover hole.
Check the clearance between the timing chain cover hole inner diameter and the inner rotor guide outer diameter.