Oil Pump: Testing and Inspection

1. Clean the following areas:
^ All parts of sludge, oil and varnish
^ Varnish may be removed by soaking in carburetor or cleaning solvent.
2. Inspect for foreign material and determine the source.
3. Inspect the pump housing and cover for the following conditions: Cracks Scoring Casting imperfections Damaged threads Do not attempt to repair the pump housing. If in doubt, replace the spring.
4. Inspect the idler shaft. If loose in the housing, replace the pump.
5. Inspect the pressure regulator valve for the following conditions:
^ Scoring
^ Sticking. Burrs may be removed with a fine oil stone.
6. Inspect the pressure regulator valve spring for the following conditions:
^ Loss of tension
^ Bending
7. Inspect the suction pipe and screen assembly for the following conditions:
^ Looseness. If the suction pipe is loose, bent or has been removed, the pump body cover and suction pipe must be replaced.
^ Broken wire mesh or screen
8. Inspect the gears for:
^ Chipping
^ Galling
^ Wear
9. Drive shaft and drive shaft extension for the following:
^ Looseness
^ Wear
10. Check for the following:
^ Gear Pocket Depth: 30.52-30.58 mm (1.202-1.204 inch)
^ Gear Pocket Diameter: 38.176-38.226 mm (1.503-1.505 inch)





11. Measure the oil pump gear lash. Install the gears, and measure in several places.
^ Gear Lash: 0.094-0.195 mm (0.0037-0.0077 inch)





12. Measure the oil pump housing gear pocket.





13. Measure the oil pump gears.

NOTE: When deciding pump serviceability based on end clearance, consider depth of wear pattern in the pump cover.





14. Measure the oil pump gear side clearance.