54. Oil Pump Clean and Inspect

Caution: Bodily injury may occur if the carburetor cleaning fluid is exposed to the skin or if the fumes are inhaled.





1. Clean all parts of sludge, oil, and varnish by soaking in carburetor or cleaning solvent.
2. Inspect for foreign material and determine the source of the foreign material.
3. Inspect the pump housing and cover for the following conditions:
^ Cracks or casting imperfections
^ Scoring (3)
^ Damaged threads
4. Do not attempt to repair the pump housing. Replace the pump housing.
5. Inspect the oil pump gears for the following conditions:
^ Scoring (1)
^ Excessive wear (2)
6. Inspect the idler shaft for looseness or scoring (4). If loose or damaged, replace the oil pump.
7. Inspect the drive gear shaft for looseness or scoring (5).





8. Inspect the pressure regulator valve for the following conditions:
^ Scoring
^ Sticking
Burrs may be removed using a fine oil stone.
9. Inspect the pressure regulator valve spring for the following conditions:
^ Loss of tension
^ Bending
10. Inspect the suction pipe and screen assembly for the following conditions:
^ Looseness.
If the suction pipe is loose, bent or has been removed, replace the pump body cover and suction pipe.
^ Broken wire mesh or screen





11. Measure the oil pump gear lash. Install the gears, and measure in several places.





12. Measure the oil pump housing gear pocket (1,2).





13. 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.

14. Measure the oil pump gear side clearance.