Testing Windshield Wiper Motors

[LockDoc]

Originally Posted by ThreeQuarter

Score another win for this 10yo thread. Helped me work through two mis-wired connectors and a poorly-grounded switch. Thanks Leon!

You can thank Ray Mcavoy, He wrote the article, I just made it available to the members of this board and answered some questions along the way.....

Originally Posted by sick472

Yeah! Thanks Leon! This thread has helped me plenty along with the many others that you have contributed too.

There is a lot of Leon in my success.

Thanks, I enjoy contributing what I can on here. Glad my contributions are helping members out with their projects....

LockDoc

[Thealien]

subscribed

[Oldironracing]

My wiper motor goes to park but when you restart it it goes down more then back up. What’s wrong with it?

[LockDoc]

Originally Posted by Oldironracing

My wiper motor goes to park but when you restart it it goes down more then back up. What’s wrong with it?

I have never heard of one doing that, so at this point I'm not sure what to tell you.....

LockDoc

[Oldironracing]

Everything seams to be in time and goes back to the same park spot when you restart wipers goes down toward the cowl.

[PepperTreeGarage]

This vid might help~~~~~ https://www.youtube.com/watch?v=HYLnGaZe6zY

[paul blair]

How is the wiper linkage? any loose bushings or parts............

[Oldironracing]

Linkage is good.

[HO455]

Great thread. Used it in my troubleshooting of "The wipers with no slow speed". Which turned out to be just the black lead on the motor being disconnected. But in the process I disassembled a non working switch I had laying around. I will post the pictures and maybe they will help someone else.

[HO455]

And more pieces.

Notice in the 3rd photo the black spots in the red circles. Those are areas damaged by arcing. The upper one is where the contacts make connection with the body of the switch.
The 4th photo shows the matching arc damage on the body of the switch.
In addition there was damaged to all three parts of the washer contacts. The last photo shows 2 of the three.

[HO455]

The 3rd part of the washer contacts, the button.
The second photo shows the contacts cleaned and almost done. (The button is just sitting there for the photo.) Notice the groove (Red arrow) I still need to repair. This amount of wear usually requires some silver solder to build up the missing material, but this time I only needed to file and buff the contract and it worked fine when tested. It being spring loaded and floating on 3 points of contact meant the the missing material wasn't critical.
The switch is pretty well engineered in that once the shaft is installed correctly (Photo 3) the rest of the parts fit only one way. That being said after 50 years of wear it was possible to reverse fit some parts due to wear. But careful inspection during reassembly will prevent this.
Notice in photo 3 the TEE on the end of the shaft. Each side of the TEE is a different size. The plastic body that holds the contacts matches the TEE, or at least it did when new.
In the 4th photo see the red and ochre lines showing the how the TEE aligns, and the green lines the alignment slots for the contact disk.
Hopefully this will help someone.

[LockDoc]

-
Thanks for the instructions on the switch. Nice addition to the thread. I have had a couple of non-working ones apart but mostly just to see how they worked. I had enough of them that I didn't worry about putting them back together..... At 40 bucks a pop for new ones this will surely help someone save some money.

LockDoc

[Hatzman]

Excellent thread!

Does anyone have a diagram that explains how to test the pump as well? My wiper motor is currently off the truck so I would like to test both systems and see if they work.

Thank you!

[LockDoc]

Originally Posted by Hatzman

Excellent thread!

Does anyone have a diagram that explains how to test the pump as well? My wiper motor is currently off the truck so I would like to test both systems and see if they work.

Thank you!

If you can post a picture of how you have it wired when testing it that would help. Basically, when you are testing the low speed you need to connect a +12v jumper to the right side pump terminal and temporarily touch a ground wire to the left side pump terminal. That should start the pump. Do not leave the ground wire connected to the left side terminal. You will have to temporarily touch the ground each time you want to restart the washer pump. The wiper motor has to be running on low speed for the washer pump to work.

You would have to have a jar with water in it and a hose connected to the large pump intake nipple. You might also have to prime the pump while it is pumping. Not sure how a person would do that with this setup. Maybe hold the jar above the pump..... If it works you might get a bath....

LockDoc

[Hatzman]

Originally Posted by LockDoc

If you can post a picture of how you have it wired when testing it that would help. Basically, when you are testing the low speed you need to connect a +12v jumper to the right side pump terminal and temporarily touch a ground wire to the left side pump terminal. That should start the pump. Do not leave the ground wire connected to the left side terminal. You will have to temporarily touch the ground each time you want to restart the washer pump. The wiper motor has to be running on low speed for the washer pump to work.

You would have to have a jar with water in it and a hose connected to the large pump intake nipple. You might also have to prime the pump while it is pumping. Not sure how a person would do that with this setup. Maybe hold the jar above the pump..... If it works you might get a bath....

LockDoc

Thank you LockDoc, That is exactly what I was looking for!

[Hatzman]

Originally Posted by LockDoc

If you can post a picture of how you have it wired when testing it that would help. Basically, when you are testing the low speed you need to connect a +12v jumper to the right side pump terminal and temporarily touch a ground wire to the left side pump terminal. That should start the pump. Do not leave the ground wire connected to the left side terminal. You will have to temporarily touch the ground each time you want to restart the washer pump. The wiper motor has to be running on low speed for the washer pump to work.

You would have to have a jar with water in it and a hose connected to the large pump intake nipple. You might also have to prime the pump while it is pumping. Not sure how a person would do that with this setup. Maybe hold the jar above the pump..... If it works you might get a bath....

LockDoc

This worked Great LockDoc,

Both my wiper and pump are working, although the pump "clicks" loudly when it starts up.. Is that normal?

[LockDoc]

Originally Posted by Hatzman

This worked Great LockDoc,

Both my wiper and pump are working, although the pump "clicks" loudly when it starts up.. Is that normal?

Well I'm not a good judge of noise because my hearing is so bad. I know they do click (that is the electromagnetic coil kicking in) then they click as long as the pump ratchet is turning, but I don't know how loud they are....

Glad the test worked for you.

LockDoc
-

[Longhorn 69]

Hi Leon, I have been bench testing the wiper motor to my 69 Longhorn, when I was testing it on the low side, and removed the neg wire from the battery it would stop on the park location.Then when running it on the high side, wired like your instructions and would remove the neg wire from the battery it would keep running but would stop and go like intermitant wipers only at high speed. I have it grounded to one of the screws holding the pump mechanisim to the motor. I removed the pump and sanded the screw locations and cleaned the terminals good. Now when in high it will stop in park when I remove the neg wire from the battery. I started testing the washer and have it wired like in your diagram and when running at low speed it will pump when I touch the neg wire to the pump terminal.When I remove the neg wire from the pump terminal it keeps pumping. I have removed both wires from the pump and when i plug in the positive wire to the motor it runs on either high or low ok, but the pump is always pumping when not even hooked up. What's up with that? I tried to load a picture but I don't think i got it attached correctly. I hope everything is going good for you. Thanks

[LockDoc]

Originally Posted by Longhorn 69

Hi Leon, I have been bench testing the wiper motor to my 69 Longhorn, when I was testing it on the low side, and removed the neg wire from the battery it would stop on the park location.Then when running it on the high side, wired like your instructions and would remove the neg wire from the battery it would keep running but would stop and go like intermitant wipers only at high speed. I have it grounded to one of the screws holding the pump mechanisim to the motor. I removed the pump and sanded the screw locations and cleaned the terminals good. Now when in high it will stop in park when I remove the neg wire from the battery. I started testing the washer and have it wired like in your diagram and when running at low speed it will pump when I touch the neg wire to the pump terminal.When I remove the neg wire from the pump terminal it keeps pumping. I have removed both wires from the pump and when i plug in the positive wire to the motor it runs on either high or low ok, but the pump is always pumping when not even hooked up. What's up with that? I tried to load a picture but I don't think i got it attached correctly. I hope everything is going good for you. Thanks

Hi Greg,

You can't leave the black ground wire connected to the pump terminal as you have it in your picture above. It should only be touched momentarily as I stated in post #164. That starts the pump. You may have damaged the pump coil or points mechanism by doing that. It could have welded the point contacts together.

LockDoc

[Longhorn 69]

Ok, and I read the whole post, and then still messed it up. I remember reading that now. This write up was such a help, and walked me right through it, then I got in a hurry. Well atleast I got the pump working good. I have another motor and pump I will have to see if I can get it pumping. Well everything else is going pretty good. Cab forward is all painted and working on getting the cab put together. Box panels all cut in and is primed and ready for filler.
Thanks Leon for your help.
Greg

[LockDoc]

Originally Posted by Longhorn 69

Ok, and I read the whole post, and then still messed it up. I remember reading that now. This write up was such a help, and walked me right through it, then I got in a hurry. Well atleast I got the pump working good. I have another motor and pump I will have to see if I can get it pumping. Well everything else is going pretty good. Cab forward is all painted and working on getting the cab put together. Box panels all cut in and is primed and ready for filler.
Thanks Leon for your help.
Greg

No problem. You can swap the pumps if you want to.

LockDoc

[Longhorn 69]

Checked out the motor and pump again yesterday morning. Well, turned out it is working properly. I was watching the ratchet lever working back and forth but the pump was not pumping until I would groung the terminal again. Also, I had another leg on the #3 terminal and was touching the neg terminal on the battery, instead of the wiper terminal. So I don't think that hurt the Pump windings. Yeah. got it put in place yesterday
Thanks again
Greg

[LockDoc]

Originally Posted by Longhorn 69

Checked out the motor and pump again yesterday morning. Well, turned out it is working properly. I was watching the ratchet lever working back and forth but the pump was not pumping until I would groung the terminal again. Also, I had another leg on the #3 terminal and was touching the neg terminal on the battery, instead of the wiper terminal. So I don't think that hurt the Pump windings. Yeah. got it put in place yesterday
Thanks again
Greg

Sounds good. Glad you got it working.

LockDoc

[6600DURAMAX]

What gives..... trying to bench test this wiper motor - dug through the old harness and found all the connectors ( added the white wire to act as a ground), even found the switch - I tried to land the yellow wire to the positive battery post and the white wire to the ground....

What am I missing

[LockDoc]

Originally Posted by 6600DURAMAX

What gives..... trying to bench test this wiper motor - dug through the old harness and found all the connectors ( added the white wire to act as a ground), even found the switch - I tried to land the yellow wire to the positive battery post and the white wire to the ground....

What am I missing

I can't really see the wiring connections in your picture but I think your problem is that you don't have the wiper switch case grounded. It has to be grounded to the battery negative along with the white wire. Watch your loose wiring when the motor starts so it doesn't get wound up in the rotating arm....

LockDoc
.