Oil Pump: Testing and Inspection

1. Place Straight Edge D83L-4201-A or equivalent across mounting surface of engine front cover (6019) and measure for wear or warpage using Feeler Gauge D81L-4201-A or equivalent. If surface is out of flat by more than 0.04 mm (0.0016 inch), replace engine front cover.
2. Check the inside of the oil pump and filter body (6603) and the inner and outer gears for damage or excessive wear.
3. Check the mating surface of the oil pump and filter body for wear. Minor scuff marks are normal but if the engine front cover, gears or oil pump and filter body surfaces are excessively worn, scored or grooved, replace the engine front cover or oil pump and filter body. Remove minor imperfections with an oil stone.

CAUTION:
Cleaning Aluminum Surfaces
Do not use abrasive grinding discs to remove gasket material; use only plastic manual scrapers. Do not scratch or gouge aluminum sealing surfaces.

4. Inspect oil pump cover gasket surface on engine front cover. Remove any gasket material, burrs or nicks. Visually inspect O-rings for any nicks and/or cuts and replace as necessary.
5. Measure thickness of gear using a micrometer. Gear should be 30.480-30.455 mm (1.20-1.19 inches) thick.
- If gear is less than specification, replace gear.
- If gear thickness is within specification, it may be necessary to replace the oil pump and filter body.
- If thickness of gear is within specified limits, go to Step 6.
6. Measure depth of the gear pocket in the oil pump and filter body. Depth should be 30.49-30.54 mm (1.200-1.202 inch).
- If depth exceeds specification, replace oil pump and filter body.
7. Measure side clearance by inserting feeler gauge between a gear tooth and side wall of the gear pocket.
- Clearance should be a maximum of 0.13 mm (0.005 inch) and gears should be free to turn.
- If clearance is greater than specification, go to Step 8.
8. Measure diameter of gear using a micrometer. Gear should be 38.252-38.332 mm (1.505-1.509 inches).
- If gear is less than specification, replace gear and measure clearance as described in Step 7.
- If diameter of gear is within specified limits, go to Step 9.
9. Measure diameter of gear pocket in the oil pump and filter body. The diameter should be 38.22-38.30 mm (1.504-1.507 inches).
- If diameter is less than specification, replace oil pump and filter body and measure clearance as specified in Step 7.