Cleaning and Inspection
CLEANINGClean all parts thoroughly. Mating surface of the chain case cover should be smooth. Replace pump cover if scratched or grooved.
INSPECTION
1. Lay a straightedge across the pump cover surface (Fig. 64). If a 0.076 mm (0.003 inch) feeler gauge can be inserted between cover and straight edge, cover should be replaced.
2. Measure thickness and diameter of rotors. If either rotor thickness measures 18.92 mm (0.744 inch) or less (Fig. 65), or if the outer rotor diameter is 82.45 mm (3.246 inch) or less. replace rotor set.
3. Slide outer rotor into chain case cover, press to one side with fingers and measure clearance between rotor and case (Fig. 66). If measurement is 0.19 mm (0.007 inch) or more, and outer rotor is within specification, replace chain case cover only.
4. Install inner rotor into case cover. If clearance between inner and outer rotors (Fig. 67) is 0.150 mm (0.006 inch) or more, replace rotor set.
5. Place a straightedge across the face of the chain case cover, 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 case cover only (Fig. 68).
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 inch). 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.