Testing Windshield Wiper Motors

[paul blair]

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

[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
.

[6600DURAMAX]

I tried to zoom in and repost pic

I'm using all the factory harness along with factory switch

The white wire I added was attached to the case screw - thought that would act as my ground