911SC eats WS washer pumps

[Dave at Pelican Parts]

My wife's 82 SC has gone through several windshield washer pumps in the last year. I am not sure if the first one was OEM or aftermarket. It froze up solid at some point, and I replaced it with a cheap aftermarket one. That one froze up after several months, and was replaced with an OEM pump by a very reputable mechanic. After a couple of months, that one has frozen up as well.

All three were tested by directly jumping the battery to the + connection of the pump, by checking for voltage across the wires to the pump when the switch was pulled, and even verifying the ground wire to the pump has good connectivity with the battery.

What is causing the pumps to seize? Do I need to run special German washer fluid? Or just water? Or is something else going on? These pumps are adding up to some real money...

--DD

[crustychief]

Maybe some junk in your washer tank?

[na2ub]

Maybe tear the pump apart and look for the cause of the failure?

[Stevepro]

I agree with Doug. Remove and dismantle the pump. You will find 2 small plastic gears, one driven by the electric motor and the other spins on a brass post. Make sure the gears and drive mechanism turn freely. You can check the operation of the electric pump motor with the pump disconnected.

The passageways in the pump are small and could be easily blocked by debris.My car sat idle for a considerable time with the washer reservoir full of water and a windscreen cleaner additive. Something in the additive caused the small filter screen on the end of the suction line to disintegrate, travel to and block the pump. I have also found algae growing in the reservoir which may also have blocked the pump if not cleaned out.

I recommend you remove the water reservoir and check for anything that could be traveling down the suction line and jamming the pump.

Good luck - Steve

[carrera turbo]

dave

not sure from reading your post but did you verify that your pump is getting 12volts to pump? if not you could be drawing to many amps and frying your pumps. also check that the tank is venting properly if not the pump will be pulling vacume while trying to pump and over working it.

cheers ed

[euro911sc]

I have been through a couple of those... as well as the headlight washer pumps... they suck. I am curious to hear of your findings!

-Michael

[McLovin]

Originally Posted by Dave at Pelican Parts

All three were tested by directly jumping the battery to the + connection of the pump, by checking for voltage across the wires to the pump when the switch was pulled, and even verifying the ground wire to the pump has good connectivity with the battery.

Your doin it wrong!

Hooking to voltage? You don't do that, you hook it to the spare tire!

C'mon Dave, you know that!

[ddubois]

Originally Posted by Stevepro

I agree with Doug. Remove and dismantle the pump. You will find 2 small plastic gears, one driven by the electric motor and the other spins on a brass post. Make sure the gears and drive mechanism turn freely. You can check the operation of the electric pump motor with the pump disconnected.

The passageways in the pump are small and could be easily blocked by debris.My car sat idle for a considerable time with the washer reservoir full of water and a windscreen cleaner additive. Something in the additive caused the small filter screen on the end of the suction line to disintegrate, travel to and block the pump. I have also found algae growing in the reservoir which may also have blocked the pump if not cleaned out.

I recommend you remove the water reservoir and check for anything that could be traveling down the suction line and jamming the pump.

Good luck - Steve

The pump on my 71 will freeze up every few months and I have to take it apart as described to free up the gears. I assume your pump is similar to my 71 pump. I think the problem is made worse if you let the reservoir go dry and the solids/minerals in the water sieze the gears.

[Dave at Pelican Parts]

Originally Posted by McLovin

Hooking to voltage? You don't do that, you hook it to the spare tire!

Oh, right--the very rare 1982 914 SC! How silly of me not to think of that!

*thwack!*

Thanks, all; I will see if I can scare up time and energy to pull the pump and disassemble it, then let you know what I find. (Hmm, time to recharge the camera batteries just in case I have any interesting results!)

--DD

[Zeke]

We don't use a lot of water in the WW system. Why not fill it with distilled water and a small amount of non corrosive cleaner? That alone may not solve the problem, but you sure will have a clean WS!