BMW 3 Series Service Manual (E39)

<6-cylinder models: Remove intake manifold to access oil pressure switch (arrow).

V-8 models: Oil pressure warning switch (arrow) is located under oil filter housing mounted to left inner fender panel.

NOTE-

Any time the oilpressure warningswitchis removed, be sure to replace the sealing washer.

Tightening torque

Oil level warning switch, replacing (6-cylinder and V-8)

4 Oil level warning switch is located at bottom of the engine oil pan.

Drain engine oil before attemptingto remove level warning switch.

Be sure to refill engine and check for leaks after work is completed.

NOTE-

Any time the oil level warning switch is removed, be sure to replace the sealing O-ring between switch and oil pan.

/LubricationSystem

Oil pump, removing and installing (&cylinder)

CAUTIOI\C

Oilpump sproclcetnut has left-handthreads. Turn clockwise to loosen.

4 Version 1, M52 oil pump assembly.

1. Oil pump pressure relief control valve

2. Oil pump suction tube

3. Suction tube support bracket

4. Oil pump assembly

5. Oil pump drive sprocltet

6. Oil pump drive chain

7. Oil pump drive sprocket nut (left hand threads)

4 Version 2, M52 TU oil pump assembly.

1. Oil pump pressure relief control valve assembly

2. Oil pump suction pick-up and seal Oil pump

Oil pump drive sprocket

Oil pump shaft locking nut (left-hand thread)

Oil pump drive chain

Version 3, M54 oil pump assembly,

10. Pickup tube sealing O-ring

11. Pickup tube

12. M6 pickup tube mounting bolts Tighten to 10 Nm (89 in-lb)

119-24

Lubrication System

Oil pump, removing and installing (V-8)

CAUTION-

V8 engines: The oilpump fasteners (including the sprocket retainingnut) are knownto vibrate loose. This can resultinoil starvation and engine failure. Be sure to checlc oil bolts and nut tighness whenever the oilpump is accessible. If any fasteners are foundto be loose, remove them andreinstallwith Loctite 8 and torque to specifications.

-Remove upper oil pan, as describedearlier, to gain access to oil pump.

4 If fitted, remove oil pump sprocket cover fasteners (arrows). Remove cover.

* Unclip oil return line (A).

4 Removeoil pump sprocket nut (arrow) and sprocket together with drive chain.

Unbolt oil pump mounting fasteners (arrows) and remove pump.

Remove oil pressure relief valve and inspect as described later.

Lubrication System

4 Replace O-ring seals (arrows) on engine oil pipes. Oil seals lightly.

CAUTIO&

Duringreinstallation, do not damage O-rings on sharp edges of engine blocl<.

4 Replace sealing O-ring (A) in oil pump.

Turn threaded spacer on pump fully to stop (arrow).

Reinstall pump. Coat pump mounting fasteners (arrows) with Loctite 8 or equivalent thread locking product. Install and tighten.

Coat pump sprocltet shafl threads with Loctite 8.Reinstall pump sprocltet with drive chain and tighten mounting nut.

119-27

Lubrication System

Oil pressure relief valve (V-8)

4 Remove oil pressure relief valve retaining circlip.

Use a suitable drift to remove relief valve assembly from pump.

CAUTION--

There is high spring pressure in the relief valve.

4 Inspect oil pump relief valve components and bore lor scoring or other damage.

1.Control plunger

2.Spring

3.Sleeve

4.Circlip

-Install using a new circlip.

Ignition System

This repair group covers component troubleshooting and replacement informationfor the ignition system.

When diagnosing engine managementproblems, including on-board diagnostics (OBD 11) fault code analysis, also refer to these repair groups:

*130 Fuel Injection

*ELE Electrical Wiring Diagrams OED On-Board Diagnostics

Special tools

System diagnosis and testing of the ignition system requires special test equipment.

4 LED test light

(Tool No. Baum 1115)

4 Automotive digital multimeter

4 Primary voltage test harness (Tool No. BMW 12 7 020)

-

4 Secondary voltage test harness (Tool No. BMW 12 7 030)