Caution: Refer to Cleaning Solvent Caution in the Preface section.
- Clean all parts of sludge, oil, and varnish by soaking
in cleaning solvent.
 
- Inspect for foreign material and determine the source of the foreign
 material.
 
- Inspect the pump housing and cover for the following conditions:
 
| •  | Cracks or casting imperfections | 
 
- Do not attempt to repair the pump housing.
 
Replace
the pump housing.
- Inspect the oil pump gears for the following conditions:
 
- Inspect the idler shaft for looseness or scoring (4).
 
If loose or damaged, replace the oil pump.
- Inspect the drive gear shaft for looseness or scoring (5).
 
- Inspect the pressure regulator valve for
 the following conditions:
 
| •  | Burrs may be removed using a fine oil stone. | 
 
- Inspect the pressure regulator valve spring for the following
 conditions:
 
- Inspect the suction pipe and screen assembly for the following
 conditions:
 
| •  | If the suction pipe is loose, bent or has
been removed, replace the pump body cover and suction pipe. | 
 
| •  | Broken wire mesh or screen | 
 
- Measure the oil pump gear lash. Install
 the gears, and measure in several places.
 
- Measure the oil pump housing gear pocket
 (1, 2).
 
- Measure the oil pump gears (1, 2).
 
Important: When deciding pump serviceability based on end clearance, consider depth
 of the wear pattern in the pump cover.
- Measure the oil pump gear side clearance.