dukenukemx

Been trying to figure out how the washer system works in my 85 928 and the headlight washer works but not the front windshield. The motor I hear for the front headlight is coming from the right side of the car but I know there's a motor in the front that I thought was for the headlight washer. So what operates the front windshield washer?

PC-85-928S

Get ready to dive into one of the most overly engineered windshield washer system ever created!
It consists of a regular washer reservoir, an intensive washer reservoir, and one way valves so the two systems do not contaminate each other. Plus the headlight washers.
Decide if you want to keep it stock (complicated) or convert to a simple system-then do some searching.
Also use a pin to make sure the hood nozzles are not clogged with wax.

WyattsRide

In the 85, I believe this is the original set up.

Main washer pump for the windshield is located on the passenger side wheel well (engine side). It pumps fluid from the main tank under the passenger side wheel well liner.
The Intensive pump is located under the Intensive fluid tank in the front of the engine. Push the little button under the dash.
The Head Light washer pump (I think) is under the main tank. That pumps the main tank fluid to the Head Lights. When they are up.

SteveG

I replaced nozzles w/new. Driver’s side (of course) still not working. A friend who makes jewelry gave a short length of surgical fine gauge wire, not sure of proper title, but it gets more rigid if you pull it over a knife edge. “Rigid” is the critical feature as it needs that to allow you to force it into the nozzle. Even though new the nozzle was blocked with crud or something during manufacturing. I had already cleaned res in wheel well and cleared all hoses feeding nozzle. Rigid wire did the trick.

mj1pate

Multiple threads exist on nozzle clogging issues. It’s worth the search. There is a steel sleeve inside the pass front fender thru which water from the main bottle (inside pass fender) must pass to get to the windshield nozzles. The sleeve rusts and rust particles clog the nozzles. Either replace the metal sleeve or place a mini-water filter in line to eliminate rust in the water stream.

dukenukemx

So there's 3 pumps? The passenger side has 2 of them? That button under the dash is meant for that? I pressed it hundreds of times and it did nothing. I gotta check that out. Looks like I gotta remove the front right wheel to get access to the windshield pump. Thanks for the info.

dukenukemx

I've read about this. Can I just remove it or does the sleeve hold it together?

The Forgotten On

The pump for the normal windshield washer is located under the coolant tank, why Porsche put it there remains a mystery.

They moved it onto the washer fluid reservoir in 87

The pump located at the front of the car is for the high intensity washer and pumps a special fluid. It'll strip wax and other things off the car so most don't bother using it or getting the fluid for it.

It is controlled by the button under the dash. It controls a relay on the board so that might have gone bad causing the non functioning issue.

Also, the factory pumps love to clog up with rust and bind for good so you're going to have to replace at least the normal washer pump.

mj1pate

I didn’t remove the sleeve but there is a thread on how to remove/cut it out. It seemed to be easier to just put an inline filter in to protect against clogging the nozzles.

gbgastowers

You can take the factory pumps apart and clean/lube them if nothing is broken. They are quite serviceable like a lot of things on this car

Rob Edwards

They disassemble with 4 small tapping screws, and are usually frozen up with crystallized washer fluid. Test the motor first on a 12V power supply- if the motor is still good then soak the pump pieces in CLR, rinse and lube with Kroil to free up the pump gears, then rinse out, blow dry, reassemble and bench test.

This pump was fine once cleaned and lubed.

dukenukemx

I know the pump works when given power, and I've also taken it apart and gave it a good cleaning and greasing. It still won't activate so I imagine it must be the relay. Where is the relay?
This is what I'm going to do tomorrow. That's a lot of corrosion in those pictures.

dukenukemx

So I took it apart today, and it sucked. The pump is located under the coolant reservoir, which I didn't know until after I took out the tank in the fender. Not that it was a bad thing because a lot of stuff needed cleaning, and I found a bad hose going to what I assume is the charcoal canister. I found the sleeves and I can see why Porsche put them in there, and that's to keep the clamp on the hose from collapsing it. I could remove them but I left them due to laziness.

The internals of the pump pretty much looked like what @Rob Edwards posted. Except that the one gear that I'd call the idle gear would be super difficult to turn. So I must have take it apart a dozen times trying to see if the motor can turn it. I polished up the gear and the brass plate that seals it and it still won't turn easy. So I took a drill and opened up the hole for the shaft of the gear and finally it turns easy enough that the motor can spin it. But the spray nozzles wouldn't spray. Turns out they're clogged. So of course I took my air compressor and used air to try and unclog them. The passenger side did unclog but not the drivers side. So I took one of the hoses off thinking that maybe one went to the other spray, but nope that was for the high intensity pump and I think I blew something up with that because the pump just leaked out all the washer fluid which was actually water. After taking apart more hoses and spray more air I was able to get the sprays to work finally. I had to abandon putting everything back together because it was late and I spent all day on this. Tomorrow I gotta remove the high intensity pump and see what I blew. Hopefully just the gasket which was old to begin with. And also put together the coolant reservoir since that's still off.

dukenukemx

Got my new to me relay and now the high intensity washer works kinda. Only one side sprays. At this point I think the check valves are stuck. Works fine with regular washer but only passenger side sprays with high intensity washer. I might as well convert it to a more sane system that needs less check valves.