Removal and installation / checking the oil pump (BMW 5 Series E39)

Removal in cars of models 520i, 523i, 528i (m52 engine)

Note: To check the operation of the safety valve, it is sufficient to first remove the oil pan; the oil pump does not need to be removed.

Remove the oil pan.



Loosen the nut and remove the oil pump sprocket together with the chain. To do this, loosen the chain tensioner (push back).

Note: The nut has a left-hand thread, so it must be unscrewed to the right.

Unscrew the bolts "arrows" of the oil pump mount and remove the pump. Pay attention to the 2 guide bushings in the cylinder block for subsequent assembly.

Move the oil pan back and remove it.

Examination

If necessary, disassemble and clean the oil pump in the following order: unscrew the fastening "2" of the inlet pipe "1", unscrew the fastening "4" of the pump cover "3" and remove the cover. In doing so, make sure that the 2 guide bushings "5" are not lost.



Check rotors "6" and "7" for wear and scratches; replace these parts if necessary.

Prescribed values of measured parameters:

• maximum radial clearance between the outer rotor "7" and the pump body "8": 0.18 mm;
• maximum axial clearance of the inner rotor: 0.08 mm;
• maximum axial clearance of outer rotor: 0.09 mm.

Remove the retaining ring "9" and pull out the safety valve, consisting of parts "10" to "13". Measure the length of the spring "12" in a free state, replace the spring if necessary. The prescribed value of the spring length: 84.1 mm.

Caution: Always replace the sealing ring "11". Carefully insert the safety valve and secure it with the retaining ring.

Screw on the intake pipe with a new sealing gasket "14", the protrusion on the gasket should face the oil receiver.

Lubricate all parts with engine oil, tighten the oil pump cover mounting bolts to a torque of 10 Nm.

Installation

Attach the oil pump, tighten bolts "15" to 20 Nm. To center the oil pump relative to the engine crankcase, there must be 2 guide bushings between them. Insert sprocket "16" with chain "17" applied and tighten fastening nut "18" (left hand thread) torque of 25 Nm. If removed, install chain tensioner "19".

Tighten the mounting bolts oil pan.