Windsheild Washer keeps running

[mhoflin]

Hey there,
I just replaced my wiper motor and switch, intermittent on 81 Silverado C10.
The washer keeps running no matter what it is set to. I turn on the wipers it starts. Anybody got an answer or experienced this?

Thanks,
Marc
SGT., US Army - Disabled

[blindbug]

Originally Posted by mhoflin

Hey there,
I just replaced my wiper motor and switch, intermittent on 81 Silverado C10.
The washer keeps running no matter what it is set to. I turn on the wipers it starts. Anybody got an answer or experienced this?

Thanks,
Marc
SGT., US Army - Disabled

You've got a short somewhere. There is a positive and negative lead to your washer pump (for my 86, it is on the back side of the fluid reservoir). Get a multimeter or a test light and connect the positive side to the positive wire of the pump lead and the negative to ground. If the light comes on, then you are getting power at a time when you shouldn't.

I would check first that the switch is wired correctly... it could just be a case of a wire going to a constant instead of the correct pump switch. Do the same test above, connecting the positive to the wire in your switch and the negative to ground to see if you get the same issue (the light comes on at an inappropriate time). If the light still comes on when the lead is connected directly to your column switch, then you're either using the wrong lead on the column switch, or you have a bad switch.

[RedBed]

Is it an aftermarket Washer/Wiper motor?

I had to exchange the one I bought 2 or maybe even 3 times because the washer pump would get stuck ON. I finally said SCREW IT and bought a separate universal pump, and hooked it up. No problems since.

[bilfman]

Had the same issue with an aftermarket one.

[hatzie]

Originally Posted by blindbug

You've got a short somewhere. There is a positive and negative lead to your washer pump (for my 86, it is on the back side of the fluid reservoir). Get a multimeter or a test light and connect the positive side to the positive wire of the pump lead and the negative to ground. If the light comes on, then you are getting power at a time when you shouldn't.

Not correct.

Why?

The 73-87 GM light truck wiper system switches the ground side of the circuit not the hot side.
The power leads on the Wiper and Washer connectors are circuit 93 in the GM wiring diagrams. These wires are always hot with the ignition on. From 79-91 circuit 93 should be the White wires.
This is my detailed post on wiper wiring in a steering column swap thread. http://67-72chevytrucks.com/vboard/s...40&postcount=8

That being said. The washer ground wire from the switch is circuit 94 in all of the 73-91 GM squarebody wiring diagrams.
Check whether the ground wire on the washer connector ( from 79-91 it's Pink ) is shorted to ground using a meter set to resistance or continuity. Attach one lead to the washer ground wire and the other to the block or some other suitable ground. If the meter reads less than infinity or it buzzes in continuity you have a short in the washer wire. Be alert. You'll let the smoke out of your meter if you hook it between the White ignition power lead and the block with the ignition on.
If you have continuity from the switched washer ground wire and the block then you have a short in that wire. If you don't then you have a borked wiper motor. It would not surprise me to hear the motor was not properly re-assembled by the re-builder.

[blindbug]

Originally Posted by hatzie

Not correct.

Why?

The 73-87 GM light truck wiper system switches the ground side of the circuit not the hot side.
The power leads on the Wiper and Washer connectors are circuit 93 in the GM wiring diagrams. These wires are always hot with the ignition on. From 79-91 circuit 93 should be the White wires.
This is my detailed post on wiper wiring in a steering column swap thread. http://67-72chevytrucks.com/vboard/s...40&postcount=8

That being said. The washer ground wire from the switch is circuit 94 in all of the 73-91 GM squarebody wiring diagrams.
Check whether the ground wire on the washer connector ( from 79-91 it's Pink ) is shorted to ground using a meter set to resistance or continuity. Attach one lead to the washer ground wire and the other to the block or some other suitable ground. If the meter read less than infinity or it buzzes in continuity you have a short in the washer wire. Be alert. You'll let the smoke out of your meter if you hook it between the White ignition power lead and the block with the ignition on.
If you have continuity from the switched washer ground wire and the block then you have a short in that wire. If you don't then you have a borked wiper motor. It would not surprise me to hear the motor was not properly re-assembled by the re-builder.

Damn, even the washer uses that backwards positive / ground setup? I know that a lot of the interior parts did that (the dome light / door switch, for instance) but didn't think that the washer pump did the same. The more you know!!!

I've been a car audio fanatic for 20 years, so know the electronics and wiring side of things well. I have to almost throw all of that out the window with the C10 due to the way grounds are used in switches and how everything wants to run through the fuseblock.

[mhoflin]

Thank you very much for all the help. In answer to the posts:

1: No, no short - I explain below
2: yes, it is aftermarket and it is the second one.

RedBed - I will never buy another aftermarket one again. I checked all the wiring and it is all good. The issue is that the parts inside do not seem to be made correctly. I ran it with the cover off and found that between the magnetic switch that activates it and the cam which is supposed to run a cycle do not match which makes the washer run continuously because the cycle of the cam does not complete and gets stuck not being able to turn the cam to complete it. Again, I will never buy another aftermarket again. I went to a junkyard and bought one that works and if I need to buy one in the future, I will opt for an authentic AC Delco.
As for what blindbug said, I too believe that it was not properly re-assembled by the re-builder.
Moral of the story; if you buy an aftermarket, do not expect it to be like new or even built correctly, it probably isn't.

Thanks again to all,
Marc
SGT., US Army - Disabled

Ma

[RedBed]

If you have the problem again, you can just bypass the washer pump and install one of these:

https://www.oreillyauto.com/detail/b...her+pump&pos=2

It has worked well for me.

[mhoflin]

Thanks, we'll do.

Thank you and God Bless you,
Marc
SGT., US Army - Disabled

[hatzie]

85 and later used a pump in the reserviour. It's mostly a drop in update. I went that route on my 76 but I wasn't doing a restoration.
The pump-on-motor washer pumps were not terribly reliable. Way too complex with a lot of moving parts.

You do have to extend the washer wires and terminate them with a two position Packard 56 plug but the reserviour is easy to fit.

[Robert Crandall]

I had that problem with my 1978. It took weeks of looking, but I finally figured out the problem is mechanical. There is a wheel with a cam that operates with the windshield wiper motor. You activate the washer, the wheel makes one revolution, and a cam turns the pump off. On mine the cam is worn, so instead of turning the pump off, it bypasses the pump switch. The only fix was to buy a new windshield wiper motor, which I will not do until I need one for the wipers. I let it pump dry maybe 20 years ago, and never filled the water bottle. It may still pump when the wipers are on.