TIMM's BMW E31 WINDSCREEN WASHER REPAIR
Right, first repair on my E31. It was
great fun on the way back from the dealers when I tried to clean the windscreen,
a little dribble of water plopped on the screen and the wipers managed to smear
it across a very small arc of the screen...great! The wiper repair is shown
elsewhere, so first to the washer system.
The first place to start is the main wash pump which is fitted to the side of the larger washer reservoir (the small one is for the intensive wash). Pulling on the washer stalk made the main wash pump run so there was no problem there. The main problem was that there was no water in the main reservoir, and bizarrely, no method of filling it up! Here's a picture of the main reservoir (I'm fiddling with the intensive wash pump):
There is only a small hole in the main tank, no lid or cap. I had to look in the owners manual to find that the filler is in the boot....so is another main reservoir! So, off we go, remove the boot carpet and spare wheel and you will find a circular reservoir (apparently only on models that have headlight washers). The system works by pumping fluid from the boot into the reservoir in the engine bay, it does this under control from the General Module when the upper tank level is low. When you operate the washers the upper pump runs until the level drops and then the lower pump keeps running (even when the washers stop) until the top tank is half-full again.
First thing to do is remove the connector to the pump and try sticking 12V up it (polarity doesn't matter):
I'm using a portable 12V battery but a pair of wires from the battery in the boot will do. Well, it clicked a bit but failed to go round so I tried 18V from an electric-drill battery, it did the same, clicked and that was it. It's time to oik out the pump. Find yourself a 5mm drill, you can use this to block up the hole that the pump leaves behind (I wish I had thought of that earlier).
Fit the connector back on the pump, it makes it easier to get a grip on the pump. Disconnect the pipe that comes from the pump where it goes into the fitting at the base of the boot. Pull the pump upwards and rotate slightly ant-clockwise so that the pipe clears the tank....and out it will pop. Put it to one side and plug the hole with a 5mm drill, there is a lot of water in that tank!
I didn't think to put a drill in the hole at the time, fortunately the boot has a drain-hole. Pump motors often seize up and there is a simple way to get them going again as long a they have not burnt-out. First pump some oil into the pump:
Now give it a good clout with the fat end of a screwdriver. Then stick a few volts in it. If it doesn't run, hit it again:
And off it goes! If yours doesn't run, you can rotate the pump-shaft with a pair of tweezers. Here, I'm giving the Intensive wash pump a good tweezering:
Don't run the pump dry for too long, just give it a few seconds to get up to speed, fill it up with oil again, and then spin it for a few seconds. Now remove the drill from the hole and immediately fit the pump back in the reservoir. Reconnect the pipe to the fitting at the base of the boot. Refit the connector and give it a go:
All done, time for a cup of tea......