Broken screws on headlight motor, how to remove them?

[Guest astro355]

I decided to tackle the passenger side headlight problem today. Besides the issue with the roller bearings being replaced with electrical tape , three of the screws were broken (2 on the cover for the plastic gear and the other holding the motor to the housing).

So is there a way to remove what is left of the screws? I briefly tried drilling the screws but didn't put more than a scratch on the screw. I really don't want to put the headlight motor back in the car that way.

Thanks,

Jim

[NCReatta]

Jim,

First, you should NEVER remove the screws that hold the motor shaft to the rest of the housing. They almost always break off, and then you have to find all the springs and brushes that will pop out, put them back in and reposition the brushes. All of which is completely unnecessary. I've rebuilt over 60 motors in the past 3 months alone and none that I have EVER rebuilt have ever needed the brushes "realigned" as some people say you need to do.

Drilling the screws out is possibly feasible if you have the correct drill bit (made to drill through metal), and a drill press.

I have never been very good at drilling things out, so most motors that break off more than one screw I just throw in the "for parts" bin. Some I will try to drill out if it's an exceptionally good looking motor, but if not I just use it for parts.

Give it a go with the good drill bits and a drill press (or a normal drill and a vice if you have one), and see what you can do. If you can't get it straightened out, I have at least a half a dozen rebuilt motors ready to ship with a lifetime limited warranty (only not warrantied if you bash it with a hammer, use it as a toy submarine, physically damage it in some other way).

Give me a call if you want to talk 1 on 1 about the problem. As it says on my business cards, "Headlight problems are our specialty!"

[Guest steveskyhawk]

The problem is that the screws are self tapping, hardened and threaded into a soft cast housing. It would be far easier and cheaper to replace that motor with a rebuilt one. I have them in my eBay store and they have a complete premium quality headlight kit already installed. Link to my eBay store is in my signature.

[Guest astro355]

Like I already said, the screws were already broken off. But you do have to take the motor off to get the plastic gear housing off. Sure, you can "gently" pry on the worm gear to slide the plastic gear housing out, but that ruins the bushings in the motor. I used to rebuild the firebird headlight motors for years and you could never get the gear out without removing the motor. Its not about realigning the brushes. I guess with the firebird motors I got lucky since I don't remember breaking off many screws at all.

I appreciate the responses but I don't see spending that much money on a used headlight motor when I have one that works that just needs some broken screws removed.

Worse case I'll just bring it with me to work (I'm a machinist) and drill it out there. Just wondering if there was another method floating in the internet.

Thanks,

Jim

[NCReatta]

It's pretty easy to get the motor gear past the motor shaft actually. When I rebuilt motors, I simply take a 3/8" and 10mm box wrenches and slide them over the motor shaft with the new bolt with the spinning washer on the end and pull straight out. Comes right out every time.

Hopefully your specialized equipment at your machine shop will be able to get them out, but as Steve said, the screws are self tapping, and will be pretty difficult to get out.

[Guest astro355]

We are going to have to agree to disagree then. I've tried stuff like that before and then removed the motor and you wouldn't believe the damage it does to the brass bushings in the motor. It puts a flat spot on it. Just saying.

[Guest Kingsley]

In the last sentence in one of your posts above, you said the magic word and that is "drill press". Since I rebuild so many motors, I have made a jig which holds the motor in perfect alignment and use a No. 29 drill which is perfect for an 8-32 retap. Before resorting to the drill and tap, I have used every known penetrant and none of them have had the slightest impact on getting the screws loose.

Since you are a machinist, there is absolutely no legitimate reason for anyone to try to sell you a new motor. Use your skills and save the motor and be many dollars ahead.

Kingsley

'89, '90 Coupe

BCA, Reatta Division

www.reattaspecialtyparts.com - Our specialties are two models of headlight motor crank arms, sun visor clips in all five OE colors and EZ On covertible tops. Our products have no equal on the market, are the best value and invite comparison!

Edited July 16, 2012 by Kingsley
Typo (see edit history)

[Guest astro355]

Thank you, I appreciate that. I was just wondering if their was a "trick" besides drilling the little bastards out.

[Barney Eaton]

Like others, I have rebuilt lots of Reatta headlight motors. If the motors come from the rust belt, you can expect several of the #8-32 hex head bolts to break. Repairing a broken screw is not a job for someone with few tools. I will share what I do.

Because I am completely rebuilding the motor, it is stripped down to the gearhousing with nothing else attached. (1) gring the broken end flat.

(2) center punch or grind a pilot hole in the broken end (centered) (3) using carbide drills, I start with a drill that is under .100 (I have several sizes and it is not that important) as I start drilling, if it is noticably off center, I stop and using a carbide burr, center the pilot hole.

(4) I drill almost all the way thru the screw, stopping before it breaks thru the back side. The reason, the screws are case hardened meaning the surface is the hardest and it gets slightly softer toward the center. If the carbide drill catches on a rough corner it breaks in the hole and now you are really screwed. (5) I step up the drill size to .125 (1/8 in) and that is very close to getting the screw body cleared. You can go a little larger if your drill is perfectly centered. (6) some options at this point, heat and penetrating oil. With most of the screw removed, it does not take as much heat to heat the remaining amount of the screw and the penetrating oil can get into at least some of the threads.

If there is a little bit of screw sticking out of the housing, it can be punched and folded over, grab with pliers and some will come out.

Last step, use a #8-32 tap and carefully chase the broken screw threads out of the housing, they usually snap off in small pieces and can be blown out with air or flushed with fluid. Then I chase the threads a second time with a new tap.

If someone has tried to repair the housing before it came to you and the screw is drilled off center or is over size, there are different types of thread inserts that will repair most of the damaged holes.

If you have a motor with broken screws do not trash it. I will take it on exchange as long as the gearhousing is not cracked or broken.

I will even buy motors with broken screws, again but the gearhousing must be good.

I charge $50 exchange to rebuild a motor + $5 shipping

Also on removing the white gear on (passanger side) I have never had a problem, I did two at the National meet in the parking lot without special tools. Ask anyone watching how it was done.

[Ronnie]

Barney, I have used your instructions in a tutorial that I just added to Reatta Owners Journal. I hope you approve. Let me know if changes are needed. If you ever take photos of the screw removal process I would like to add them to the tutorial.

Headlight Motor Broken Screw Removal

[Guest astro355]

Thanks for all of the replies. I went into work early and drilled out the screws with carbides. Piece of cake really.