Oil Pump: Inspection

Install inner rotor (drive gear) and outer rotor (driven gear) into pump housing. Place straightedge across pump housing and both gears. Using feeler gauge, check rotor gears-to-housing clearance.
With rotors installed, check outer rotor-to-inner rotor clearance (between gears). Check clearance between outer rotor and housing. Remove outer rotor. Measure outer rotor diameter and thickness. Check pump cover for flatness.
Measure relief valve spring free length. Using spring pressure tester, check spring pressure. Spring pressure should be 20 lbs. (9 Kg) when compressed to a height of 1.34" (34.0 mm). Replace oil pump assembly if measurements are not within specification. See OIL PUMP SPECIFICATIONS table.

OIL PUMP SPECIFICATIONS

Application

In. (mm)

Outer Rotor O.D.

2.469 (62.71)

Outer Rotor Thickness

.9435 (23.965)

Outer Rotor-to-Housing

.014 (.35)

Outer Rotor-to-Inner Rotor

.008 (.20)

Pump Cover Flatness

.003 (.07)

Rotor Gears-to-Housing ⁽¹⁾

.0010-.0035 (.025-.088)

Valve Spring Free Length

1.95 (49.5)

⁽¹⁾	Measured by using straightedge across housing.