Oil Pump: Service and Repair

Fig. 36 Oil pump disassembled:

DISASSEMBLY
1. Remove oil pump drive shaft extension, Fig. 36. Do not attempt to remove washers from drive shaft extension. The drive shaft extension and washers are serviced as an assembly.
2. Remove cotter pin, spring and pressure regulator valve, Fig. 36. Apply pressure on pressure regulator bore before removing cotter pin since the spring is under pressure.
3. Remove oil pump cover attaching screws, then oil pump cover and gasket.
4. Remove drive gear and idler gear from pump body.

INSPECTION
1. Check gears for scoring or other damage, replace if necessary.
2. Proper end clearance is .0005-.0075 inch.
3. Check pressure regulator valve, valve spring and bore for damage. Proper bore to valve clearance is .0025-.0050 inch.
4. Check extension shaft ends for wear.

ASSEMBLY
1. Install gears and shaft in oil pump body.
2. Check gear end clearance by placing a straight edge over the gears and measure the clearance between the straight edge and gasket surface. If end clearance is excessive, check for scores in cover that would bring the clearance over specified limits.
3. Install cover and torque attaching screws to 7 ft. lbs.
4. Install pressure regulator valve, closed end first, into bore, then the valve spring and cotter pin.