Washer Pump Repairs
E31, E32 and E38
My Intensive pump had not been working for a while, it made a slight noise when the stalk button was pressed so electricity was getting to it. The main problem with the intensive wash operation is that it rarely used, water creeps past the lower pump seal and the pump-motor becomes seized. However, it is usually quite easy to get the motor running again.
The first method is to connect power to the pump motor in one direction and then in reverse. For this I use a portable battery with a couple of leads, however any 12V battery will do. Unplug the pump connector and connect 12V across the terminals, if the motor does not run reverse the wires. Try swapping polarity a few times, if it fails to start you can try a few more volts, here I am using an 18V portable-drill battery:
If that fails to get the pump going it is time to remove the pump from the tank. Arm yourself with a 5mm drill, refit the connector to get better purchase on the motor and twist and pull the pump upwards, it will pop out of the tank. Immediately fit the drill in the hole so you do not lose all the water (I'm using a screwdriver with a 5mm shaft here):
You can now use a pair of tweezers or fine-nosed pliers to carefully rotate the pump shaft:
Once the shaft is rotating, spray some WD40 to penetrate the lower seal and connect power back to the motor, it will spin quite fast. Now drop some engine oil down the pump shaft and run the motor again. Here I am oiling the rear pump on an E31:
Once the pump is running smoothly refit the pump back in the reservoir and check that the washer operation operates reliably. I have done the same fix on both my E38 and E31 and they are still running well. I like cheap fixes!