Removal and installation the oil pump — engines M20, M30 and M50 (BMW 5 Series E34)

Removal

Disconnect the ground wire from the battery.

Caution: When the battery is disconnected, the information in the electronic memory devices, such as the engine fault memory or the radio security code memory, is erased. When disconnecting the battery, follow the instructions in the section "Removing and installing the battery".

Remove the oil pan.



Engines M30, M50: Unscrew the nut, remove the sprocket together with the chain, having first removed the chain tensioner.

Please note: The nuts on the M50 engine have left-hand threads.

Unscrew the oil pump "arrows".

Pull out the oil pump. In this case, on the M30 engine, pay attention to the position of the spacer plates between the oil pump and the engine block. On the M50 engine, pay attention to the position of both centering bushings.

Installation

Check the oil pump.

Insert the oil pump and tighten the bolts to a tightening torque of 20 Nm.

Engines M20, M30: Screw on the sprocket with the chain applied. Install the tensioner.

Install the oil pan.

Fill the engine with oil. The marks on the rod indicate the oil level in the engine. The difference between the min and max marks is 1 liter.

Lower the car.

Connect the ground wire to the battery.

After a test drive, check the oil pan for leaks and, if necessary, carefully tighten all bolts.

Checking the oil pump

Remove the oil pump.



Remove cover 1 of the oil intake. Pull out mesh 2 and wash it in fuel.

Turn the drive shaft and check the ease of movement of the gears.

Unscrew the oil pump cover "arrows" and remove the gears.

Check the body and cover for cracks and the gears for wear.



Remove the overload protection valve by squeezing it with special pliers and pulling out the retaining ring 4.

Note: Washer 5 is pressed by the valve spring, so it should be held with a suitable rod or key head. Pull out the spring and piston 6.

Check the ease of movement of the piston in the housing.

Measure the length of the compression spring. The specified value of the spring length in a free state: 44+0.2 mm.

Insert the piston, spring 3 in figure W - 1608, and washer and hold with a screwdriver.

Insert the retaining ring.

Tighten the oil pump cover with a tightening torque of 9 Nm.

Put the lid on.

Install the oil pump.

(The original material is located on the website «bmwman.ru»)