Headlamp motor won't stop running
Thread Starter
Drifting
Joined: May 2003
Posts: 1,647
Likes: 28
From: Woodbridge NJ
Headlamp motor won't stop running
I took the 84 to a car show this evening and when I turned the lights off the left headlamp motor continued to run. When the lights are on, all is fine. If I place the switch to running lights only, the motor will turn off. The motor runs only when the lights are turned off.
When the light switch is turned off, there is a little play in the headlamp assembly, it doesn't close completely. I disconnected the power to the motor for now.
I searched my Helms, but unfortunately the manual dosen't expalin much about the headlamps. If it does, I haven't located it as of yet.
I should add the car has been sitting for quite a while, but has never had a headlamp motor issue.
Any help is appreciated.
When the light switch is turned off, there is a little play in the headlamp assembly, it doesn't close completely. I disconnected the power to the motor for now.
I searched my Helms, but unfortunately the manual dosen't expalin much about the headlamps. If it does, I haven't located it as of yet.
I should add the car has been sitting for quite a while, but has never had a headlamp motor issue.
Any help is appreciated.
Thread Starter
Drifting
Joined: May 2003
Posts: 1,647
Likes: 28
From: Woodbridge NJ
If this were the case, would the lamp open fine as it does now? When the lights are tuned off the assy remains opened about a 1/2 inch as the motor runs.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
when mine did as you described, it still opened and closed the door, after it was closed the motor would still run on for about 20 seconds ...for awhile, then finally stopped. When I tore it apart I found dust for bushings.
Last edited by mseven; Oct 10, 2007 at 09:28 PM.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
I have never been into my headlight motor assemblies, But as I understand it, there is a "limit switch", a pair of contacts that break the circuit and shut off the motor when it reaches the end of it's travel. I would think that if the gears were stripped, the lights either wouldn't move or would move only partially. The bushings that commonly fail might cause a misalignment that could prevent the switch from working as it should. Like I said, I've never been in there. I didn't look in my FSM, but I would only expect to find R&R procedures for the mechanisms. I don't know where you would find repair instructions for the components.
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Thread Starter
Drifting
Joined: May 2003
Posts: 1,647
Likes: 28
From: Woodbridge NJ
I have never been into my headlight motor assemblies, But as I understand it, there is a "limit switch", a pair of contacts that break the circuit and shut off the motor when it reaches the end of it's travel. I would think that if the gears were stripped, the lights either wouldn't move or would move only partially. The bushings that commonly fail might cause a misalignment that could prevent the switch from working as it should. Like I said, I've never been in there. I didn't look in my FSM, but I would only expect to find R&R procedures for the mechanisms. I don't know where you would find repair instructions for the components.
RACE ON!!!
RACE ON!!!
I'm not one who is in favor of making good money bad. I'll post my findings.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
it will be easy enough to know once you open it up. If the delrin bushings are disentigrated, it will feel jammed to take the gear ***. apart. Also look for flattened/worn off teeth on the outside of the gear.
Melting Slicks
Joined: Jul 2003
Posts: 2,384
Likes: 124
From: Reno/Sparks Nevada
I'm assuming this is an early headlight motor which uses gears and limit switches. These early motors didn't use delrin bushings in the gears but they did use plastic gears and a rubber insert in the gear to dampen the torque effect on the gear when the headlight hit the stops. If the motor didn't actually rotate to the full open or closed position the motor is still in a state of rotation. It's only when the motor hits the stops is torque applied to open the contacts inside that stops current from flowing. If the motor is turning but not the headlight assembly then it could be stripped gears inside the motor. I wouldn't rule out a bad mechanical connection between the motor which is attached to the headlight and the actual headlight assembly. You didn't mention if the gears sounded like they were stripping. Have you tried pushing on the headlight assembly while the motor is running? This might cause a stripped gear to engage and you'll either hear or see the headlight assembly try to move. If you can eliminate a bad mechanical connection then removing the entire assembly and removing the motor from the assembly may be your next step. Attached is a link to a site that details removal of the headlight and motor. I'd be interested in seeing what you find. Good luck.
http://automobiletest.com/service/19...ghts/index.htm
Art
http://automobiletest.com/service/19...ghts/index.htm
Art
Thread Starter
Drifting
Joined: May 2003
Posts: 1,647
Likes: 28
From: Woodbridge NJ
Art,
Thank you, after doing some research , I found that the 84 does have gears and limit switches. The headlamp will open completely and remain open, when the headlamp switch is turned off, the headlamp goes down, but remains open about an inch or so and the motor remains running. The inch or so that remains open, has play in it and moves freely. If I press on the flap to close it, it will open up to the inch mentioned. I should mention, I hear no grinding noise.
I'll venture off to the site know. Your help is deeply appreciated.
Excellent link.
Thank you, after doing some research , I found that the 84 does have gears and limit switches. The headlamp will open completely and remain open, when the headlamp switch is turned off, the headlamp goes down, but remains open about an inch or so and the motor remains running. The inch or so that remains open, has play in it and moves freely. If I press on the flap to close it, it will open up to the inch mentioned. I should mention, I hear no grinding noise.
I'll venture off to the site know. Your help is deeply appreciated.
Excellent link.
Last edited by Brimis; Oct 12, 2007 at 07:59 PM.
Thread Starter
Drifting
Joined: May 2003
Posts: 1,647
Likes: 28
From: Woodbridge NJ
I'm assuming this is an early headlight motor which uses gears and limit switches. These early motors didn't use delrin bushings in the gears but they did use plastic gears and a rubber insert in the gear to dampen the torque effect on the gear when the headlight hit the stops. If the motor didn't actually rotate to the full open or closed position the motor is still in a state of rotation. It's only when the motor hits the stops is torque applied to open the contacts inside that stops current from flowing. If the motor is turning but not the headlight assembly then it could be stripped gears inside the motor. I wouldn't rule out a bad mechanical connection between the motor which is attached to the headlight and the actual headlight assembly. You didn't mention if the gears sounded like they were stripping. Have you tried pushing on the headlight assembly while the motor is running? This might cause a stripped gear to engage and you'll either hear or see the headlight assembly try to move. If you can eliminate a bad mechanical connection then removing the entire assembly and removing the motor from the assembly may be your next step. Attached is a link to a site that details removal of the headlight and motor. I'd be interested in seeing what you find. Good luck.
http://automobiletest.com/service/19...ghts/index.htm
Art
http://automobiletest.com/service/19...ghts/index.htm
Art
Turned out to be the large gear. About 20 % of the gear is striped which is the reason the lamp would not completely close.
I'm going with the plastic gear as opposed to the brass. In my opinion, if something should happen to the brass gear, the entire assembly could get damaged. The plastic gear lasted 23 years. I'll worry about it in another 23 years.
Thank you
Melting Slicks
Joined: Jul 2003
Posts: 2,384
Likes: 124
From: Reno/Sparks Nevada
I've not seen a stripped gear in these early motors. I think I have read about it. I wonder what caused it? Your choice to go back to a plastic gear is a good one. Unless something caused the headlight assembly to stop I don't know how the gear would strip. It might be something to look at when you remove/replace the assembly. I did have my headlight stop because one of the screws that held the headlamp cover on had backed out and when the headlight rotated the screw hit the hood and caused it to stop. This isn't the flat cover you see when the headlight is closed it's the one you see when the headlight is open. Good luck I hope you get it working soon.
Art
Art
Instructor
Joined: Sep 2007
Posts: 192
Likes: 0
From: Waynesville North Carolina
Turned out to be the large gear. About 20 % of the gear is striped which is the reason the lamp would not completely close.
I'm going with the plastic gear as opposed to the brass. In my opinion, if something should happen to the brass gear, the entire assembly could get damaged. The plastic gear lasted 23 years. I'll worry about it in another 23 years.
Thank you
I'm going with the plastic gear as opposed to the brass. In my opinion, if something should happen to the brass gear, the entire assembly could get damaged. The plastic gear lasted 23 years. I'll worry about it in another 23 years.
Thank you
My 85 did the same thing a few weeks ago, left side had stripped gear, I went ahead and replaced both sides, with plastic also.saved a ton of money because of all the help from the forum guys
