Oil Pump: Service and Repair

Fig. 9 Oil Pump Disassembled:

REMOVAL
1. Remove oil pan as described under OIL PAN.
2. Remove pump to rear main bearing cap bolt and remove pump and extension shaft.

DISASSEMBLY
1. Remove pump cover attaching bolts and pump cover, Fig. 9.
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 pickup tube and screen assembly are to be replaced, mount pump cover in a soft jawed vise and remove pickup tube from cover. Do not remove screen from pickup 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 pickup tube and screen assembly for damage.
6. Check pressure regulator valve for fit in pump cover.

Fig. 10 Oil Pump Screen Installation:

ASSEMBLY
1. If pickup tube and screen were removed, apply sealer to end of pickup tube, then mount pump cover in a soft jawed vise and using pickup screen and tube installer tool No. J-21882, Fig. 10, tap pickup tube into position using a plastic mallet. Whenever the pickup tube and screen assembly have been removed, a new pickup tube and screen assembly should be installed. Use care when installing pickup 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, Fig. 9.
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. Tighten bolts to specifications.
6. Rotate pump driveshaft 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.