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Dan Ogle

Headlight motor

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Most likely the 3 plastic rollers inside the motor are shot...they get ground into powder.   The powder cannot get out it creates a lot of slop...I suspect when you turn on the lights there is a hesitation before they open, also when they close.    Once open or closed the motor would normally stop but because the motor can push the powder around they keep running until the headlight controller times them out.

 

You can open the motors and replace the rollers........if your car is from the south none of the small screws will break, but if you live in the rust belt, at least one will be frozen and you will break the 10-32 screw.

I am attaching a picture of the inside of the motor with good and bad rollers.

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Probably the headlight control module if they are opening and closing normally otherwise The headlight control module is located up in the drivers fender behind the air cleaner housing. It senses the current draw by the motors and shuts them off at end of stroke when the current consumption increases quickly as the motor encounters resistance.

This approach eliminated the need for limit switches on the headlamp assemblies to stop travel at full up or down. However, if the current sensing portion of the circuit in the module fails the symptom you are having will often be the result. If allowed to go like this it will damage the motors, the mechanisms or burn up the module. You may want to use the headlamp retract button (88/89 models only) to keep them up instead of running them up and down them as needed until this is fixed as it will reduce wear and tear on the associated parts.

All that said I believe this run-on of the motors could also happen if either the delrin bushings inside the gear box are broken or the keyed opening in the crank arm is getting rounded out as these would both reduce the resistance on the motor at the end of the up stroke. However, either or both of these problems will generally result in the headlamp(s) not popping up at all. Pretty sure the headlight control module has a time out where it will kill power to the motors after they run "x" number of seconds too long for an up or down cycle to have completed normally.

EDIT: I see Barney already had a go at this while I was typing. Hopefully his explanation is correct, as the bushings are readily available while the control module is getting harder to find and is more costly in any case.

KDirk

Edited by KDirk (see edit history)
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The reason/logic to stating it is the rollers.....If it was the bellcrank, it would just be sloppy until the flatted hole completely rounded. 

At that time the doors would not open because the motor shaft would just spin in the bellcrank hole.

 

I don't think it is the headlight module.....they seldom fail and when they do, the doors don't open.

 

As a refresher for new Reatta owners here is a picture of factory bellcranks (arms) look at the hole.    New/good bellcranks have two parallel flats.  The steel motor shaft wears against these flats in the softer bellcrank if the nut is loose.    The second phase ....the hole starts to look like a "bow tie",  finally the hole completely rounds and the motor shaft spins.

 

Factory (soft) bellcranks have been obsolete for at least ten years, when last available they listed for $135 (included a link)

Today three vendors sell steel replacement bellcranks, prices vary quite a bit, but all work fine and should last forever.

If you think you need a "factory" looking bellcrank, Kingsley Baker sells a factory unit with a steel insert.

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First off thank you both for answering,and Secondly,Where might I purchase the internal parts Barney shows or can they be bought over the counter ?

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Fireostore.com has what you need, either a complete kit or just the rollers (pins). 87-88 Fiero is very similar (think only the motor mount is different.)

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If you need bellcrank arms as well, Kingsley at Reatta Specialty Parts sells these as well as full kits with rollers and new upstop hardware (this eliminates the jitter often seen when driving and the headlight pods vibrate). He sells both a repro arm - that looks different but works perfectly -and reworked originals with a stainless insert in place of the rounded out flatted shaft hole. I've purchased his kits and can fully endorse their quality. You may also check the gaskets on your motors. Sometimes they are deteriorated. I have bought new gaskets kits off ebay, these are precision die cut cork gaskets, one for the motor housing and one for the gear housing.

KDirk

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Corvette folks sell the Delrin rollers. Been awhile but $5 sounds like something I'd remember.

As for the Fiero/ Reatta headlight mechanisms being similar; I remember the Fiero headlight doors opening rather slowly compared to the instant Reatta assembiles.

Why?

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Early (84-86) Fieros were the most common and used a different control system. Late (87-88) have the same gutz and controllers are intechangable. Also Firebird and Corvette of the same period.

Edited by padgett (see edit history)
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Over the years I have found many items used in place of the original plastic rollers.   Some of them are ball bearing, nuts, spray nozzle from paint can, and silicone sealant filling the area.

I think GM designers original idea was the plastic rollers would act as clutches in the event the headlight doors were stuck open or shut.

 

I have thought about alternatives.....the plastic rollers are cheap and readily available.  

If there is enough torque in that area to break and crush plastic I would think the same thing would happen to wood.

Also the original parts were .490 dia just under 1/2 inch making it a problem to use 1/2 stock plastic, wood or metal......I was using 1/2 inch plastic at one time that I ground down to the smaller diameter but

I had more in labor than it cost to buy parts from outside vendors......which I do now.

 

It is your car and you can use anything you want, I would think the wood dowel material would be soft (good) but it also has a grain and I suspect it will split over time.

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my pass side went bad a couple weeks ago.  I installed a kdirk rebuild and is working great.

A piece of the bracket broke off on me where the plastic up stop screw goes in, ticked me off, cause I was almost done. 

I got to brainstorming and figured I'd try and come up with a fix, so I drilled and tapped a hole in the alum bracket right next to where it broke.. Installed a screw in my new hole, adjusted it and tightened it down with a stop nut, then put a rubber vacuum cap over the head of the screw to act as a "bumper".

its been working perfect.  I should've took a picture of it, lol!  With the painted metal body piece put back on, you can't even see it

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