Oil Pump: Service and Repair
Fig. 20 Oil pump exploded view. 4-151:
1982 - 87, 4-151 Liter
REMOVAL
1. Drain crankcase, then remove oil pan as described under ``Oil Pan, Replace.''
2. Remove two oil pump mounting bolts and nuts from main cap bolt and remove oil pump and screen as an assembly.
DISASSEMBLE
1. Remove four pump cover to body attaching screws, then remove cover, idler and drive gears and shaft.
2. Remove pin, retainer, spring and pressure regulator valve.
INSPECTION
Inspect pump components and should any of the following conditions be found, the oil pump assembly should be replaced.
1. Inspect pump body for cracks and excessive wear.
2. Inspect oil pump gears for damage, cracks or excessive wear.
3. Check shaft for looseness in housing.
4. Check cover for wear that would allow oil to leak past ends of gears.
5. Check oil pick screen for damage to screen or relief grommet. Also remove any debris from screen surface.
6. Check pressure regulator valve for fit in body.
Fig. 20 Oil pump exploded view. 4-151:
ASSEMBLE
1. Place drive gear and shaft in pump body, then install idler gear with smooth side of gear facing pump cover.
2. Install and torque pump cover attaching screws to 105 inch lbs. Check to ensure that pump rotates freely.
3. Install pressure regulator valve, spring, retainer and pin.
INSTALLATION
1. Align oil pump shaft with tang on oil pump drive shaft, then install pump on block, positioning pump flange over oil pump drive shaft lower bushing.
2. Install oil pump mounting bolts and torque bolts to 20 ft. lbs., then install oil pan as described under ``Oil Pan, Replace.''
1988
REMOVAL
1. Remove engine from vehicle.
2. Remove oil pan assembly, refer to ``Oil Pan, Replace'' procedure.
3. Remove balancer assembly, then the filter body.
4. Remove pump gears, then the pressure regulator valve.
SERVICE
This engine uses a gerotor type oil pump. The oil pump is serviced only as an assembly with the balancer assembly. Installation
Reverse removal procedure.
V6-173
REMOVAL
1. Remove oil pan as described under ``Oil Pan, Replace.''
2. Remove pump to rear main bearing cap bolt and remove pump and extension shaft.
Fig. 21 Oil pump exploded view. V6-173:
DISASSEMBLY
1. Remove pump cover attaching bolts and pump cover.
2. Mark drive and idler gear teeth so they can be installed in the same position, then remove idler and drive gear and shaft from pump body.
3. Remove pin, spring and pressure regulator valve from pump cover.
4. If pick-up tube and screen assembly are to be replaced, mount pump cover in a soft jawed vise and remove pick-up tube from cover. Do not remove screen from pick-up tube, these components are serviced as an assembly.
INSPECTION
1. Inspect pump body and cover for excessive wear and cracks.
2. Inspect pump gear for damage or excessive wear. If pump gears are damaged or worn, the entire pump assembly must be replaced.
3. Check drive gear shaft for looseness in pump body.
4. Inspect pump cover for wear that would allow oil to leak past gear teeth.
5. Inspect pick-up tube and screen assembly for damage.
6. Check pressure regulator valve for fit in pump cover.
Fig. 21 Oil pump exploded view. V6-173:
ASSEMBLY
1. If pick-up tube and screen were removed, apply sealer to end of pick-up tube, then mount pump cover in a soft jawed vise and using tool No. J-8369, tap pick-up tube into position using a plastic mallet. Whenever the pick-up tube and screen assembly has been removed, a new pick-up tube and screen assembly should be installed. Use care when installing pick-up tube and screen assembly so that tube does not twist, shear or collapse. Loss of a press fit condition could result in an air leak and a loss of oil pressure.
2. Install pressure regulator valve, spring and pin.
3. Install drive gear and shaft in pump body.
4. Align marks made during disassembly, then install idler gear.
5. Install pump cover gasket, cover and attaching bolts. Torque bolts to 6 to 9 ft. lbs.
6. Rotate pump drive shaft by hand and check pump for smooth operation.
INSTALLATION
1. Assemble pump and extension shaft with retainer to rear main bearing cap, aligning top end of hexagon extension shaft with hexagon socket on lower end of distributor shaft.
2. Install pump to rear main bearing cap bolt.
3. Install oil pan as described under Oil Pan, Replace.