Inspection

Figure 84 Oil Pump:

CLEANING
Clean all parts thoroughly. Mating surface of the chain case cover should be smooth. Replace pump cover if scratched or grooved.

Figure 85 Checking Oil Pump Cover Flatness:

INSPECTI0N AND REPAIR
1. Lay a straightedge across the pump cover surface. If a 0.076 mm (0.003 inch) feeler gauge can be inserted between cover and straight edge, cover should be replaced.

Figure 86 Measuring Outer Rotor Thickness:

2. Measure thickness and diameter of rotors. If either rotor thickness measures 18.92 mm (0.744 inch) or less, or if the outer rotor diameter is 82.45 mm (3.246 inch) or less, replace rotor set.

Figure 87 Measuring Outer Rotor Clearance In Housing:

3. Slide outer rotor into chain case cover (CCC), press to one side with fingers and measure clearance between rotor and CCC. If measurement is 0.19 mm (0.007 inch) or more, and outer rotor is within specification, replace CCC only.

Figure 88 Measuring Clearance Between Rotors:

4. Install inner rotor into CCC. If clearance between inner and outer rotors is 0.150 mm (0.006 inch) or more, replace rotor set.

Figure 89 Measuring Clearance Over Rotors:

5. Place a straightedge across the face of the CCC, in between the bolt holes. If a feeler gauge of 0.077 mm (0.003 inch) or more can be inserted between rotors and the straightedge, and the rotors are within specification, replace the CCC only.
6. Inspect oil pressure relief valve plungers for scoring and free operation in its bore. Small marks may be removed with 400 grit wet or dry sandpaper.
7. The relief valve springs have a free length of approximately 49.5 mm (1.95 inch) and should test between 22.5 and 24.5 pounds when compressed to 34 mm (1 - 11/32 inches). Replace spring that fails to meet specifications.
8. If oil pressure is low and pump is within specifications, inspect for worn engine bearings or other reasons for oil pressure loss.