2004 E53 3.0 D Auto - screen wash issue - anyone got any ideas

[Smeeagain]

Ok, so there are three ways to activate the screen wash
Push the stalk away - get the rear wash
Pull the stalk towards you - direct front screen and headlamps wash as required.
Push button on end of stalk and you get a double hit of screen wash a couple of seconds apart.

Now,..... the rear wash works fine every time.

But, ....... when I pull the stalk towards me for regular front wash, sometimes nothing happens for maybe as much as five seconds. Sometimes the same thing happens with the button on the end of the stalk. I noticed if I get nothing by pulling the stalk towards me then if I switch to pressing the button on the end it works first time. but the opposite is true, press the button on the end of the stalk, get nothing then switch to pulling the stalk towards me and it works first time. In each instance when I get no screen wash I can hear the pump working so I know they work

Now originally I thought there was a blockage, so I pulled all the pumps out, removed the tank and emptied it, and removed the filters. Everything was clean with no gunk - not really a surprise as I clean it out a couple of times a year. I've pulled the pipes and there appears to be no blockages there.

So the only thing I can think of, is an air lock in the two pumps, or a blockage inside the pumps themselves.

Can anyone think of anything else, and/or can anyone give any tips on removing the blockage/air lock. it's not the end of the world so i don't plan on replacing them (and suspect they'd be expensive anyway.

Cheers
Smee

[fenj66]

i take it youve tried swapping the front and rear pumps over to see what happens then? or just swap the electical connectors.

[X5-D-Sport]

You may possibly have blocked filters in the washer bottle...
The fluid grows jelly in the bottom of the washer bottle over time & blocks the filters.... there may be a one way valve that's failed, often half way up the pipe from the bottle to the screen.

As our friend above suggests, you can always swap the pipe & connections to the adjacent pump & check for a lazy pump motor... but check for the filth in the filters any way....

Remove the washer tank, remove pumps & pull out the black o-ring looking things... these have the filters on the inside.... if gooey, flush them out under a tap, wash & flush the water tank too & fill with fresh washer fluid.

[Smeeagain]

[quote="X5-D-Sport Salisbury"]
You may possibly have blocked filters in the washer bottle...
The fluid grows jelly in the bottom of the washer bottle over time & blocks the filters.... there may be a one way valve that's failed, often half way up the pipe from the bottle to the screen.

As our friend above suggests, you can always swap the pipe & connections to the adjacent pump & check for a lazy pump motor... but check for the filth in the filters any way....

Remove the washer tank, remove pumps & pull out the black o-ring looking things... these have the filters on the inside.... if gooey, flush them out under a tap, wash & flush the water tank too & fill with fresh washer fluid.
[/quote]

So .... thank you for taking the time to reply, but I have to ask, did you actually read the bit where I said Id taken out the filter, or did you just choose to ignore it ....

[Smeeagain]

Ok, so as a bit of an update

There are three pumps on the screen wash reservoir - two identically sized ones to the rear of the reservoir, and one  larger one on the front nearside of the reservoir.

The rear one on the offside (drivers side) is for the rear screen wash, and the one on the nearside (passenger side) is for the front screen. The larger front one is for the headlamp wash. I determined this by removing the tank and holding each pump as someone else sat in the car and activated, rear, front, headlamp etc (headlamp pump only works if lights are on). I could feel the vibration within each pump as it was activated so i knew which was which. I have no idea why the headlamp wash needs such a noticeably larger pump. I then swapped over the connectors so the rear pump activated the front screen and so on.

It appears that the front screen and headlamp pumps are both lazy/defective.

The good news is that the smaller pumps are around £7 delivered on eBay and the larger one is about a tenner or so. So both are ordered and on their way.

Smee

[X5Sport]

Headlight washers are higher pressure and there are four of them, hence larger pump needed.

[Smeeagain]

Makes sense, thanks

[Smeeagain]

I finally closed out this problem so thought I would report back.

I identified that the rear screen wash and headlamp screen wash always worked, it was only the front screen one that failed randomly.
This led to me to the following potential issues.

Issue with the electric on the stalk on the steering column, but I could always hear the pump motor working so there was power getting to it, so I ruled that out.

Filter in reservoir blocked - no, checked and cleaned and regular

Air lock or blockage in pump or dodgy pump (I could hear the motor going) - replaced pump still had issue.

Nozzle blocked - unlikely as I could get water through it when it was working and neither nozzle was receiving water.

Air lock in pipe from pump to screen wash nozzle.

Blockage in pipe from pump to screen wash nozzle.

So to address the last two points,, I went into our local motor factors and bought a light of tubing (clear so I can see any blockages or air locks on future. Did it at the side of the road outside the shop, and hey presto, screen wash instantly working and has stayed working ever since.

Cost £1.50