Oil Pump: Service and Repair

OIL PUMP

REMOVAL

1. Disconnect negative cable from battery.
2. Remove timing belt.
3. Remove timing belt rear cover.
4. Remove oil pan.

Fig. 81 Crankshaft Sprocket Removal:

5. Remove crankshaft sprocket using Special Tools 6793 and C-4685-C2.

Fig. 82 Crankshaft Key:

6. Remove crankshaft key.
7. Remove oil pick-up tube.

Fig. 83 Oil Pump:

8. Remove oil pump and front crankshaft seal.

DISASSEMBLY

1. To remove the relief valve, proceed as follows:

Fig. 84 Oil Pressure Relief Valve:

a. Remove the threaded plug and gasket from the oil pump.
b. Remove spring and relief valve.

Fig. 85 Oil Pump:

2. Remove oil pump cover fasteners, and lift off cover.
3. Remove pump rotors.
4. Wash all parts in a suitable solvent and inspect carefully for damage or wear.

CLEANING
Clean all parts thoroughly in a suitable solvent.

INSPECTION

Fig. 86 Oil Pump:

1. Inspect the mating surface of the oil pump. Surface should be smooth. Replace pump cover if scratched or grooved.

Fig. 87 Checking Oil Pump Cover Flatness:

2. Lay a straightedge across the pump cover surface. If a 0.025 mm (0.001 in.) feeler gauge can be inserted between cover and straight edge, cover should be replaced.

Fig. 88 Measuring Outer Rotor Thickness:

3. Measure thickness and diameter of outer rotor. If outer rotor thickness measures 9.40 mm (0.370 in.) or less, or if the diameter is 79.95 mm (3.148 in.) or less, replace outer rotor.

Fig. 89 Measuring Inner Rotor Thickness:

4. If inner rotor measures 9.40 mm (0.370 in.) or less replace inner rotor.

ASSEMBLY

1. Assemble pump, using new parts as required. Install the inner rotor with chamfer facing the cast iron oil pump cover.
2. Prime oil pump before installation by filling rotor cavity with engine oil.
3. Install cover and tighten fasteners to 12 Nm (105 in. lbs.).

CAUTION: Oil pump pressure relief valve must be installed correctly or serious engine damage may occur.

4. Install relief valve, spring, gasket and cap. Tighten cap to 41 Nm (30 ft. lbs.).

INSTALLATION

1. Make sure all surfaces are clean and free of oil and dirt.

Fig. 90 Oil Pump Sealing - Typical:

2. Apply Mopar Gasket Maker to oil pump as shown. Install 0-ring into oil pump body discharge passage.

3. Prime oil pump with engine oil before installation.
4. Align oil pump rotor flats with flats on crankshaft. Install the oil pump to the block.

CAUTION: To align, the front crankshaft seal MUST be out of pump, or damage may result.

Fig. 91 Front Crankshaft Seal Installation:

5. Install new front crankshaft seal using Special Tool 6780.

Fig. 82 Crankshaft Key:

6. Install crankshaft key.

CAUTION: The crankshaft sprocket is set to a predetermined depth from the factory for correct timing belt tracking. If removed, use of Special Tool 6792 is required to set the sprocket to original installation depth. An incorrectly installed sprocket will result in timing belt and engine damage.

Fig. 92 Crankshaft Sprocket Installation:

7. Install crankshaft sprocket using Special Tool 6792.
8. Install oil pump pick-up tube.
9. Install oil pan.
10. Install timing belt rear cover.
11. Install timing belt.