9 - 50
ENGINE 3.9L
OIL PUMP
REMOVAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump from rear main bearing cap.
DISASSEMBLE
(1) Remove the relief valve as follows:
(a) Remove cotter pin. Drill a 3.175 mm (1/8 in.)
hole into the relief valve retainer cap and insert a
self-threading sheet metal screw into cap.
(b) Clamp screw into a vise and while support-
ing oil pump, remove cap by tapping pump body
using a soft hammer. Discard retainer cap and
remove spring and relief valve (Fig. 57).
Fig. 57 Oil Pressure Relief Valve
1 - OIL PUMP ASSEMBLY
2 - COTTER PIN
3 - RELIEF VALVE
4 - RETAINER CAP
5 - SPRING
(2) Remove oil pump cover (Fig. 58).
(3) Remove pump outer rotor and inner rotor with
shaft (Fig. 58).
(4) Wash all parts in a suitable solvent and inspect
carefully for damage or wear.
CLEANING
Use only mild solvents to clean the oil pump. Do
not use any abrasive material to clean the oil pump
housing or rotors.
INSPECTION
Mating surface of the oil pump cover should be
smooth. Replace pump assembly if cover is scratched
or grooved.
Fig. 58 Oil Pump
1 - INNER ROTOR AND SHAFT
2 - BODY
3 - DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 - COTTER PIN
5 - RETAINER CAP
6 - SPRING
7 - RELIEF VALVE
8 - LARGE CHAMFERED EDGE
9 - BOLT
10 - COVER
11 - OUTER ROTOR
Lay a straightedge across the pump cover surface
(Fig. 59). If a 0.038 mm (0.0015 in.) feeler gauge can
be inserted between cover and straightedge, pump
assembly should be replaced.
Fig. 59 Checking Oil Pump Cover Flatness
1 - COVER
2 - STRAIGHT EDGE
3 - FEELER GAUGE
BR/BE