Engine Overhaul Manual v8 4.0 4.6
ENGINE
26
OVERHAUL
Oil pump - inspection
1. Thoroughly clean oil pump drive gear, cover
plate, rotors and housing. Remove all traces of
sealant from threads of cover plate securing
screws and bolt; ensure tapped holes in timing
cover are clean and free from oil.
2. Check mating surfaces of cover plate, rotors
and housing for scoring.
3. Assemble rotors and oil pump drive gear in
housing ensuring that reference marks are
aligned.
4. Using feeler gauges, check clearance between
teeth of inner and outer rotors:
Maximum clearance = 0.25 mm (0.01 in)
5. Remove oil pump drive gear, check depth of
any wear steps on gear teeth:
Wear step maximum depth = 0.15 mm (0.006
in)
6. Place a straight edge across housing.
7. Using feeler gauges, check clearance between
straight edge and rotors:
Maximum clearance = 0.1 mm (0.004 in).