Oil Pump: Testing and Inspection

Oil Pump Cleaning and Inspection

Cleaning

- Clean all parts thoroughly in a suitable solvent.

Inspection

- Disassemble oil pump. Refer to => [ Oil Pump ] Overhaul.

- Clean all parts thoroughly. The mating surface of the oil pump housing should be smooth. Replace the oil pump cover if scratched or grooved.






- Lay a straightedge (1) across the pump cover (3) surface. If a 0.025 mm (0.001 in.) feeler gauge (2) can be inserted between the cover (3) and the straight edge (1), the cover (3) should be replaced.






- Measure the thickness and diameter of the outer rotor. If the outer rotor thickness measures 14.299 mm (0.563 in) or below, or if the diameter is 79.78 mm (3.141 in) or less, replace outer rotor.






- Measure the thickness of the inner rotor. If the rotor measures 14.299 mm (0.563 in) or less replace the inner rotor.






- Slide the outer rotor (2) into the body, press the rotor to one side with your fingers and measure the clearance between the rotor and the body using a feeler gauge (1). If the measurement is 0.39 mm (0.015 inch.) or more, replace body only if the outer rotor is within specifications.






- Install the inner rotor (3) into the outer rotor (2). Using a feeler gauge (1), measure the clearance between the inner and outer rotors. If the clearance is 0.20 mm (0.008 inch.) or more, replace both the rotors.






- Place a straightedge (1) across the face of the body, between bolt holes. If a feeler gauge (2) of 0.077 mm (0.003 in) or more can be inserted between the rotors and the straightedge, replace the pump assembly only if the rotors are within specifications.






- Inspect the oil pressure relief valve (1) plunger for scoring and free operation in its bore. Small marks may be removed with 400 grit wet or dry sandpaper.

- The relief valve spring (2) has a free length of approximately 49.5 mm (1.95 in) it should test between 101 to 110 N (23 to 25 lbs) when compressed to 34 mm (1.34 in). Replace the spring that fails to meet specifications.

- Assemble the oil pump. Refer to => [ Oil Pump ] Overhaul.