Testing the window motors
Thread Starter
Instructor
Joined: May 2021
Posts: 160
Likes: 27
From: Yukon, OK
Testing the window motors
I am installing a new power window harness in my '68 and have no idea if the window motors are any good or not. Any suggestions on the best way to go about testing these while still attached to the door and regulator? Thanks in advance for the help!
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
The 2-connector plug on those motors are for the UP and DOWN power. Electrical ground for those motors is attached to the motor housing.via a separate single black ground wire with a screw. You can just use some jumper wiring to connect ONE of the connector pins and housing ground to a 12 vdc battery to see if it works OK. Move the + wire over to the other connector to check the reverse motor rotation.
Melting Slicks
Joined: Dec 2016
Posts: 3,193
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From: Central Bucks County, Pennsylvania
And pray to God you don’t have to pull those motors out! Getting the mounting bolts threaded back in for reinstalling is a major pain in the *** when you don’t have little girl hands!
Thread Starter
Instructor
Joined: May 2021
Posts: 160
Likes: 27
From: Yukon, OK
The 2-connector plug on those motors are for the UP and DOWN power. Electrical ground for those motors is attached to the motor housing.via a separate single black ground wire with a screw. You can just use some jumper wiring to connect ONE of the connector pins and housing ground to a 12 vdc battery to see if it works OK. Move the + wire over to the other connector to check the reverse motor rotation.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Lee,
Now you have to find the REAL cause of your problems. Until you identify a viable cause, you have nothing to fix. Wish you luck. Just check-out the possible items in that list. Good hunting!
Now you have to find the REAL cause of your problems. Until you identify a viable cause, you have nothing to fix. Wish you luck. Just check-out the possible items in that list. Good hunting!
Thread Starter
Instructor
Joined: May 2021
Posts: 160
Likes: 27
From: Yukon, OK
So I was able to determine that the window motors were of the 1976-1982 vintage. My question now is if the doors likely came off of a '76-'82 or if for some reason, someone would replace both window motors with later model equipment. That doesn't really seem likely to me, but who knows. I will really need to determine the year of the doors before buying any missing pieces. Any thoughts or help is appreciated. Lee
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If the doors don't have the 1968 push button AND finger flap on them, and you don't have to have the "correct" doors on it, fix what has to be repaired on them. One method of determining which year doors you have might be the mirror mounting for the driver's door. I believe the '76 cars still had the old-style metal mirrors (maybe '77, too). Thereafter, the "Sport" mirrors were installed at the factory. If the mounting points are different for those two mirror styles, maybe you can narrow down the true vintage of your doors. But, since I don't know the mounting details, I can't help there. Good luck.
Last edited by 7T1vette; Aug 31, 2021 at 11:18 AM.
Thread Starter
Instructor
Joined: May 2021
Posts: 160
Likes: 27
From: Yukon, OK
If the doors don't have the 1968 push button AND finger flap on them, and you don't have to have the "correct" doors on it, fix what has to be repaired on them. One method of determining which year doors you have might be the mirror mounting for the driver's door. I believe the '76 cars still had the old-style metal mirrors (maybe '77, too). Thereafter, the "Sport" mirrors were installed at the factory. If the mounting points are different for those two mirror styles, maybe you can narrow down the true vintage of your doors. But, since I don't know the mounting details, I can't help there. Good luck.
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Thread Starter
Instructor
Joined: May 2021
Posts: 160
Likes: 27
From: Yukon, OK
So, to recap, I installed a new '68 power window harness and discovered that the window motors that were installed had a different connector and so determined that they were 1977-82 era motors. I bought pigtails that connected the '68 harness to the later model motor...EXCEPT..that there is no place to connect the ground wire. The '68 harness plug has three wires, blue, brown and black. Blue and brown to the motor connector and apparently there was a separate blade on the opposite end of the motor for the ground. The pigtail only accepts two wires. I guess 77-82 does not have that ground wire? Question is, what do I do with the ground from the '68 harness? I assumed that I could just change out the end to an eyelet and screw it to the door but when I called Letric Limited to ask their opinion, I was told that I absolutely positively had to ground it to the motor itself, but there is no blade to connect it to... Has anyone run into this before? I called and talked to Vovette as well and they were as puzzled as me. Ideas?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If you are saying that the pigtail you have has the ground wire already in it, just connect to that ground wire (black?) and run it to one of the screws on the motor's metal casing. You also need to verify that the other end of that 'ground' wire actually goes to a good solid piece of metal that connects with the frame/birdcage. The grounding connection for those motors is the metal casing. If you wish, you can attach a 1/4" male spade terminal to one of those screws and put a female 1/4" spade terminal on the end of the ground wire.