Oil Pump Inspection

Check the oil jet for damage or clogging.
If necessary, repair the cylinder block.

Check the relief valve.

1. Coat the valve with engine oil, and then check that the valve falls smoothly into the valve hole by its own weight.
   If it does not, replace the relief valve. If necessary, replace the oil pump assembly.
   

Check the side clearance.

1. Using a feeler gauge and precision straightedge, measure the clearance between the rotors and precision straightedge.
   

   Standard clearance:

   0.100 to 0.170 mm (0.0039 to 0.0067 in.)
   

   Maximum clearance:

   0.325 mm (0.0128 in.)
   

   If the side clearance is greater than the maximum, replace the oil pump assembly.
   

Check the tip clearance.

1. Using a feeler gauge, measure the clearance between the drive and driven rotor tips.
   

   Standard clearance:

   0.080 to 0.160 mm (0.0031 to 0.0063 in.)
   

   Maximum clearance:

   0.35 mm (0.0138 in.)
   

   If the tip clearance is greater than the maximum, replace the oil pump assembly.
   

Check the body clearance.

1. Using a feeler gauge, measure the clearance between the driven rotor and pump body.
   

   Standard clearance:

   0.100 to 0.170 mm (0.0039 to 0.0067 in.)
   

   Maximum clearance:

   0.325 mm (0.01128 in.)
   

   If the body clearance is greater than the maximum, replace the oil pump assembly.
   

Using vernier calipers, measure the length of the 8 links with the chain fully stretched.

Maximum chain elongation:

52.4 mm (2.063 in.)

HINT:

Make the same measurements pulling at 3 or more places selected at random.

Wrap the chain around the oil pump sprocket.

Using vernier calipers, measure the sprocket diameter with the chain.

NOTICE:

Vernier calipers must contact the chain rollers for measuring.

Minimum sprocket diameter (with chain):

Crankshaft 48.2 mm (1.898 in.)

Oil pump drive shaft 48.2 mm (1.898 in.)

Measure the chain tensioner plate wear.

Maximum wear:

0.5 mm (0.020 in.)