Window Washers aint working! W108 - PeachParts Mercedes-Benz Forum

Californian SE · #1 09-19-2008, 04:40 AM

Hey,
The pump for the water to my window washers isnt working. The tank is full, pipes are clean, and everything seems ok. Not sure what it could be, and I've never had a 108 before, and seeing as they werent working when i purchased the car i dont know what to expect. I presume they work when you push the pedal (where a clutch would normally be) inside the car to activate them.

Any help is appreciated, cheers Luke

Jengasan · #2 09-19-2008, 11:39 AM

Cali SE

Yep that's what the little pedal on the floor is for. Have you checked the fuses in the bank under the dash ? there should be a card in there telling you which is which and if memory serves it's one of these - Right hand side on mine but I have RHD. If they are ok, get a voltage tester (or a bulb ?) and check for 12v at the little pump on the tank when somebody pushes the predal, if you get 12v the pump is probably goosed but check for dirty connections - I've had a lot of these ! I actually doubt the pump is expensive to replace anyway. If you don't get 12v you either have a switch or wiring fault between switch/pump/powerfeeds. Have fun.

J

cdplayer · #3 09-19-2008, 01:30 PM

There could be variations to the pump location. I removed the entire window washing mechanism for a customer from a 1972 280SE and the pump motor was built into the foot pump. No motor at the tank. If not a fuse, perhaps the motor is rusty(seized). Or the electrical connection at the foot pump is bad. See pics

ja17 · #4 09-20-2008, 12:51 AM

Hello,

I believe all the W108 are simply a bladder and switch as pictured. Stepping on the pedal compresses the bladder squirting fluid through the lines. The electrical part of the unit is a switch to activate the wiper motor. Remove the unit and make sure it is not ruptured. You can bench test it before putting it back in.

250 Coupe · #5 09-20-2008, 09:48 PM

If it is the bladder type, you can try to fix it with silicone like I did. That way, you can find out how much windshield washer fluid your carpet can hold when it is siphoned out by the leak you didn't see.

Michael

Larry Delor · #6 09-21-2008, 11:57 PM

Those bulbs are known to fill up with crud. Remove the unit, and give it a good shaking and rinsing out. Don't squeeze it too hard if there is resistance....you don't want to break the bulb - just work with it, and get things cleaned out.

Good Luck

250 Coupe · #7 09-22-2008, 06:52 AM

If it is the bladder type, there is a check valve in the cap on the fluid tank. It won't work if the valve is stuck.

I checked fastlane and it lists the manual bladder type pedal assembly for the 108 at $119.

Michael

Californian SE · #8 09-25-2008, 06:39 AM

hey, sorry guys but its not a bladder system. Its definately all electrically pumped. Took the pedal and pump set up appart today, cleaned all points etc, and it sure is electric. Im still not sure why its not working though. The windscreen whipers move, but no water sprays the screen.
cheers,
luke

ja17 · #9 09-25-2008, 07:14 AM

Hello,

The electrical part of the unit is the switching mechanism for the wipers. You should also have a little rubber bladder with two small hoses hooked to it?

Maybe someone changed it with a non original? As far as I know all the W108 cars had the same arrangement?

Californian SE · #10 09-28-2008, 04:52 AM

Sorry but it just cant be. I know they're in original condition because there has only been two owners, my grandfather and I.
Also, with the original pedal there is no spot for any valve, and there is no line out for the air.
There are two motors places near the battery in the engine which are aimed at providing pressure to the line which is connected to the water tank.
It's definately an entirely electric system.

Tomguy · #11 09-28-2008, 02:09 PM

Your grandfather had someone replace or update the system. All 108's (All!) had the bladder system where pumping with your foot is what made the fluid go to the windscreen. If the wipers turn on when you use the foot pedal, then something is wrong with the electric pump or the wiring to it. Check the pump by giving it 12v and see if it shoots, it can rule out the pump as the culprit or verify it as the cause.

Jengasan · #12 09-29-2008, 05:47 AM

Quote:

Originally Posted by Tomguy

Your grandfather had someone replace or update the system. All 108's (All!) had the bladder system where pumping with your foot is what made the fluid go to the windscreen. If the wipers turn on when you use the foot pedal, then something is wrong with the electric pump or the wiring to it. Check the pump by giving it 12v and see if it shoots, it can rule out the pump as the culprit or verify it as the cause.

Sorry Tomguy but I have to disagree on this one. My car is fitted with an electrical pedal switch which operates the wipers AND a small electrical pump located on the large VDO washer reservoir under the bonnet (hood) - all OEM fitted. Admittedly mine is a european car but it's close to CAL SE's in age (mine's a '71 V8) and I'm banking from his description that it's the same set up. After looking at his posts again I would still bet there's a connection off between the pump and switch or the pump is dead as originally suggested.

mercmad6.3 · #13 09-29-2008, 06:19 AM

Hi,You have the same washer pump set up as all euro and right hand drive W108 -109's? .Do you have the metal pedal ?. Check the pump .It will be under the hood . A 4" long plastic body with a couple of hoses on the square bit on the end.
Disassemble the end part and you will see a couple of small gears. Clean everything and make sure the motor turns easily by hand.
Reassemble and run it off the battery to test. Check the nozzle on the cowl vent to make sure it's clear. i pull them off and poke a needle into the holes to push stuff backwards out of the nozzle.
The pump draw fluid from the tank and pushes it up to the nozzle. Very simple in operation. BUT,if the system is working But not pumping the wipers should still give two strokes before self parking. No wiper movement means the fuse has blown . It's very rare for the switch o fail in the pedal . If it has failed I have good used ones here.

Californian SE · #14 09-30-2008, 07:01 AM

Sorry Tomguy, im not only going to dissagree with you, but I know for a fact you're wrong. Perhaps your countries export line had the bladder system, but I've seen hundreds of W108's here in Australia and not a single one on a bladder system. Most right hand drives are electrical.

Tomguy · #15 09-30-2008, 07:45 AM

Very interesting! Well, glad to be proven wrong; at least this way it's easy to get parts for it if the motor turns out dead!