Oil Pump: Service and Repair

Fig. 12 Oil Pump Exploded View:

REMOVAL
1. Remove oil pan as outlined.
2. Remove bolts securing pump to block and the oil pump and screen assembly.

DISASSEMBLY
1. Remove four cover retaining bolts and the cover, Fig. 12.
2. Mark position of drive gear and rotor to ensure proper assembly.
3. Remove drive gear and rotor from body.
4. Remove pin, spring and pressure regulator valve.Do not remove oil pump pickup and screen assembly. If pickup tube is loose, or if tube or screen are damaged or clogged, oil pump should be replaced.

INSPECTION
1. Inspect pump body for cracks, scoring and excessive wear.
2. Inspect gears for cracks, excessive wear and damage, and check shaft for looseness in housing.
3. Inspect inside of cover for wear and scoring that would allow oil to leak past ends of gears.
4. Check fit of relief valve in bore, checking for looseness or binding.
5. If any components are damaged or excessively worn, or if pickup assembly is loose or damaged, oil pump assembly should be replaced.

ASSEMBLY
1. Install pressure relief valve, spring, and spring retaining pin.
2. Install drive gear and shaft.
3. Install idler gear in pump body with smooth side toward pump cover opening.
4. Align marks made during disassembly.
5. Install gasket, cover and retaining screws and tighten to specifications.

INSTALLATION
1. Prime pump with engine oil or pack with petroleum jelly.
2. Align slot in pump shaft with tang on driveshaft.
3. Install pump on block, positioning flange over oil pump driveshaft lower bushing, then tighten mounting bolts to specifications.
4. Reinstall oil pan as outlined.