Oil pump and its drive chain — removal, inspection and installation (BMW 3 Series E46)

Oil pump

Note: During installation, it will be necessary to replace the oil pickup pipe sealing rings and the pressure relief valve plugs, as well as the pressure relief valve spring ring.

Removal and installation

1. Remove the pan as described in the previous paragraph.

2. Unscrew the nut securing the sprocket to the pump shaft. Note that the nut has a left-hand thread (Fig. 13.2).



3. Remove the sprocket and chain from the pump shaft.

4. On models where the pump is combined with an oil separator, unscrew the bolts and remove the separator together with the pump and oil intake pipe.

5. On models where the oil pump and damper are made separately, unscrew the two bolts securing the oil intake pipe to the oil damper and one bolt securing the pipe to the pump (Fig. 13.5). Remove the pipe.



6. Unscrew the four pump mounting bolts and remove the pump from the engine (Fig. 13.6).

Inspection

7. Unscrew the pump cover bolts and remove the cover (Fig. 13.7).



8. Remove the rotors from the pump.

9. Inspect the pump body, cover and rotors for wear, scoring and cracks. If any defects are evident, replace the rotors or the pump assembly depending on the severity of the defect. It is recommended to replace the entire pump.

10. Insert the rotors into the pump housing and use feeler gauges to measure the gap between the outer rotor and the housing. Place a steel ruler on the pump housing with its edge and use feeler gauges to measure the gap between the ruler and each rotor (i.e. axial clearance of the rotors in the housing) (fig. 13.10,a,b). Compare the results obtained with the Technical Data and, if necessary, replace worn parts or the entire pump.







11. To disassemble the pressure reducing valve, lightly press the valve into the housing with some metal tool and remove the spring ring from the upper part of the housing (fig. 13.11).

Caution! There is a tight spring in the valve. Be careful when removing the spring ring.

12. Remove the plug, spring and plunger from the valve body (fig. 13.12,a-c).









13. Place a new sealing ring on the valve plug, then assemble the valve in the reverse order of disassembly. Secure the valve parts with a new snap ring.

14. Place the rotors into the pump body, then install the cover, screw in the bolts and tighten them to the specified torque.

15. Otherwise, the pump installation is carried out in the reverse order of removal, taking into account the following notes.

• a) Replace the oil pickup pipe sealing ring.
• b) Tighten the pump sprocket mounting nut (with left-hand thread) the required moment.

Oil pump drive chain

Removal

16. Remove the primary timing chain (see paragraph 7).

17. Remove the oil pump chain from the crankshaft sprocket.

Inspection

18. Perform the operations described in paragraph 7 for the secondary camshaft chain.

Installation

19. Place the chain on the crankshaft sprocket, then install the primary chain as described in paragraph 7.

The original is located on the internet portal «www.bmwman.ru»