Headlight motor rebuild problem!
Thread Starter
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Headlight motor rebuild problem!
Ok, I rebuilt the headlight motor, cleaned and greased, put it back together and nothing. It worked before but was really slow. I checked to make sure it isn't binding. Checked the plug and it's getting power. What did I do? Ant way to check it out of the car? Thanks 
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
Good grief. You built the thing and didnt check it before you put it back in? All you have to do is ground the case and touch the terminals with the positive wire off a battery or charger. One makes the motor go CW and the other CCW.
Melting Slicks
Joined: Jul 2004
Posts: 3,497
Likes: 127
From: Kissimme now from LI,NY
if you know your getting power to the motor, I would look and make sure that the brushes are good or on correctly.. That's where I would start.. If I'm correct, someone else stated you can use a battery charger.. Ground to the case and power to the motor tabs...
Race Director
Joined: Jul 2002
Posts: 11,593
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From: Clayton NC
Tech Contributor
Joined: May 2005
Posts: 15,576
Likes: 118
From: Conroe Texas
Exactly. And that's why I get confused when I see that my headlight motor behavior is seemingly dependent upon the integrity of those tattle tail switch wires.
Thread Starter
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Made sure the black ground wire was connected to the frame in the nose and the casing of the headlight motor. Might have got some grime or something on the brushes. Will take it apart, clean the brushes with alcohol and see what happens. Can I just use a 12 volt battery to check it off the car? Ground the body to the ground on the battery and use the hot to either of the motor terminals?
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Drifting
Joined: Dec 2006
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From: Jackson California
2023 C2 of the Year Finalist - Modified
Made sure the black ground wire was connected to the frame in the nose and the casing of the headlight motor. Might have got some grime or something on the brushes. Will take it apart, clean the brushes with alcohol and see what happens. Can I just use a 12 volt battery to check it off the car? Ground the body to the ground on the battery and use the hot to either of the motor terminals?
That's exactly the correct way to test it out of the car.Good luck in resolving your concern. Chris
Safety Car
Joined: Feb 2003
Posts: 4,068
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From: St. Joseph Mo
Always run 'em on the work bench before putting them back in. Run foreward and reverse for 4-5 minutes each way. They will get very hot. Seats the motor brushs and polishes the commutator.
Hope you didn't use an over long #10-24 screw for the brace/ground wire. A long screw there and you short out the field winding.
Hope you didn't use an over long #10-24 screw for the brace/ground wire. A long screw there and you short out the field winding.
Thread Starter
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Thanks guys, some good information here. I will check the ground screw length, and check it with a battery. If it still doesn't work, I will open it up and wipe the brushes with some alcohol to make sure my dirty hands didn't contaminate the brushes while putting them back together. Yep, will double check to make sure I put them back in the correct position too. My eyes aren't that good anymore. 
The other motor was rebuilt recently but makes kind of a screeching noise while turning the headlight bucket. I checked the bucket when the motor was out and it was free and no noise. Any ideas? I don't think it's the motor but maybe the bar that keep the motor in place?
The other motor was rebuilt recently but makes kind of a screeching noise while turning the headlight bucket. I checked the bucket when the motor was out and it was free and no noise. Any ideas? I don't think it's the motor but maybe the bar that keep the motor in place?
Safety Car
Joined: Feb 2003
Posts: 4,068
Likes: 27
From: St. Joseph Mo
I forgot something.
Motor shaft endplay adjustment.
There is a small headless slotted end screw with a jam nut on the gear train housing. Set it for just a tiny bit of endplay of the armature.
Too much endplay and the brushs will climb up on the armature under load.
There is a small headless slotted end screw with a jam nut on the gear train housing. Set it for just a tiny bit of endplay of the armature.
Too much endplay and the brushs will climb up on the armature under load.
Thread Starter
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Advanced
Joined: Apr 2005
Posts: 99
Likes: 2
From: Overland Park KS
You could also try backing off the two screws that hold the motor housing on. Sometimes the first time you start them up it helps that they're a little loose. Once it's running you can snug them up again.
Pro
Joined: Jan 2007
Posts: 524
Likes: 12
From: Auckland New Zealand
Thanks guys, some good information here. I will check the ground screw length, and check it with a battery. If it still doesn't work, I will open it up and wipe the brushes with some alcohol to make sure my dirty hands didn't contaminate the brushes while putting them back together. Yep, will double check to make sure I put them back in the correct position too. My eyes aren't that good anymore.
The other motor was rebuilt recently but makes kind of a screeching noise while turning the headlight bucket. I checked the bucket when the motor was out and it was free and no noise. Any ideas? I don't think it's the motor but maybe the bar that keep the motor in place?
The other motor was rebuilt recently but makes kind of a screeching noise while turning the headlight bucket. I checked the bucket when the motor was out and it was free and no noise. Any ideas? I don't think it's the motor but maybe the bar that keep the motor in place?
I've done mine recently and had an awful lot of trouble with the left hand headlight turning real slow. The motor sounded as though it was struggling both before the rebuild and after.
The problem I found was a combination of two things. The end float of the motor shaft and also the thickness of the washer behind the bellville washer on the main output gear. I used a thinner washer here - about half thickness of standard. I found that the standard washer jammed the pot metal gear when the casing was screwed together tight - don't ask me why. Now both motors open quick and together
Thread Starter
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Ken,
I've done mine recently and had an awful lot of trouble with the left hand headlight turning real slow. The motor sounded as though it was struggling both before the rebuild and after.
The problem I found was a combination of two things. The end float of the motor shaft and also the thickness of the washer behind the bellville washer on the main output gear. I used a thinner washer here - about half thickness of standard. I found that the standard washer jammed the pot metal gear when the casing was screwed together tight - don't ask me why. Now both motors open quick and together
I've done mine recently and had an awful lot of trouble with the left hand headlight turning real slow. The motor sounded as though it was struggling both before the rebuild and after.
The problem I found was a combination of two things. The end float of the motor shaft and also the thickness of the washer behind the bellville washer on the main output gear. I used a thinner washer here - about half thickness of standard. I found that the standard washer jammed the pot metal gear when the casing was screwed together tight - don't ask me why. Now both motors open quick and together
I was wondering about that also. I don't know why there is a thick washer and a convex washer. It would seem the one convex would be enough to make good alignment with the worm gear. I might try removing the thick washer and see what happens.
Thread Starter
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Advanced
Joined: Apr 2005
Posts: 99
Likes: 2
From: Overland Park KS
The screeching is probably a lubrication issue unfortunately. It's probably in one of the rotor bushings. They need to be cleaned really well and lubricated with a little lithium grease (or whatever).
If you can run the motor while tightening the two housing screws you can get the the optimum bolt tightness.
These motors are essentially the same as the 65 66 power antennas. I've done a ton of those and have seen most of the problems.
If you can run the motor while tightening the two housing screws you can get the the optimum bolt tightness.
These motors are essentially the same as the 65 66 power antennas. I've done a ton of those and have seen most of the problems.
Thread Starter
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Well, both motors are now installed and working. I am going to ignore the screeching because I don't use headlights much since I usually don't drive at night. BUT, if I need to I now have working headlights! Thanks everyone for the help. It's nice to know if I need to drive at night, I can. But I think if they fail again, I will just exchange them for re-built. Yep, costs a little extra but I noticed the Little gear was worn and pretty much on both sides so turning 180* isn't going to work.
