- Clean the oil pump components in cleaning solvent.
 
Caution: Refer to Safety Glasses Caution in the Preface section.
- Dry the components with compressed air.
 
- Inspect the gears (427, 428) for the following conditions:
 
- Inspect the oil pump housing (422) for the following conditions:
 
| •  | Damaged bolt hole threads | 
 
| •  | Worn oil pump driveshaft bore | 
 
| •  | Scoring or excessive wear within the housing | 
 
- Inspect for a collapsed pressure relief valve spring.
 
- Inspect the pressure relief valve for scoring or wear. The valve should move freely within the bore of the housing.