C2 Headlight Motor Diagnosis, Test, and Repair Process

[Harry S.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

I've been working with Rich about timing the motors. Mine are 5 seconds to turn 180 degrees and the other is 8 seconds to turn 180 degrees. This is on the bench. In post 14 rich displays the thickness of the washer/spacer at .06 thick. I started up the grinder and the washer/spacer that turned at 8 seconds is now .04 thick. Each of the motors now turn 180 degrees in 5 seconds. Success, but the washer/spacer is no longer smooth. Smooth is better.

Anyway have a source for this washer/spacer at the .04 thickness. The ID is .50 and the OD is 1.0.

Cheers

[Richard G.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Harry;
PM me. I can machine one for you at no cost.
I just need to know the material you want it manufactured from.
I have nylon, aluminum or steel.
Rick

[Harry S.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Rick, thanks

PM Sent

[Richard M.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Another option is to shave the face of the gear, but only on a lathe for ideal accuracy.

I've done that many times.

Rich

[Harry S.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Think I'm done. Got them both to turn 180 in 4 seconds.

1) New Grease
2) One new Gear
3) One used armature, mine was broken at the shaft
4) Polished the brushes and armature with 1500 grit black sandpaper
5) one has a washer of .06, the other is .04

[Richard M.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Think I'm done. Got them both to turn 180 in 4 seconds.

1) New Grease
2) One new Gear
3) One used armature, mine was broken at the shaft
4) Polished the brushes and armature with 1500 grit black sandpaper
5) one has a washer of .06, the other is .04

Harry, Good work and thanks for the update. Now the real tough part.... Getting them back in the car.

Leaning over to get them in can be tough on your back.

Rich

[Harry S.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Harry, Good work and thanks for the update. Now the real tough part.... Getting them back in the car.

Leaning over to get them in can be tough on your back.

Rich

Warm enough in the garage today, both motors reinstalled. Same speed going down, the right is about 1 second slower coming up.

Just need to put the grille in and clean it for a ride this weekend.

Cheers!

[Richard M.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Like button!

[Richard M.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

I'm adding to this thread with some videos and information. I have several motors here I'm going through for a buddy and have made a playlist on one motor on my YT channel for you to follow along if you want to tear into yours some day.

Click the Play All button. It's a start to finish of a motor that wouldn't run. It turns out it was dry and had a bad gear.

It's a Playlist and will advance through 11 videos in sequence as I tore into it. Sorry for some jitters and off view clippings holding the dUmbphone camera. lol

Click "Play All"

https://www.youtube.com/playlist?list=PLCc04e4BJ8b81hh3H0gck01lNgfFWxSo0

[Owen L.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Well explained, thank you!

I noticed that other than the armature shaft coming through the case, these are very much the same as the power window motors for the C2 & through the C3 years. Tests, maintenance, and clean-up is identical.

[Jeffrey S.]

Re: C2 Headlight Motor Diagnosis, Test, and Repair Process

Earlier today I took my spare Headlight motor assembly and did some tests and moving the infamous steel gear washer around in the gearcase. Here are 2 videos. They're long, around 5 minutes each.

I also took more measurements of my gear collection at different places and some calculations to show what the tolerances are inside the gearcase to accommodate the gears. I will be adding that information to the thread when I get time.

Videos...

This one has the steel gear washer in the "GM illustrated" location. It's a Dog.

This has the steel washer behind the conical washer, opposite of the "GM illustrated" location. It's a Cheetah.

If anyone here has direct experience about this oddity and has input I'd appreciate all feedback, any flavor............
........ Joe R. @ JRP ??? Brian T. @ CS_of_MW ??? Ernie @ Wilcox ??? Jay M. @ JM ??? Others ????

Thanks,
Rich

Hey Richard:

I came across an older post you made regarding the placement sequence of the steel washer and the conical washer in the headlight motor gearbox. I tried reversing the sequence of the two washers, as you did, by placing the steel washer behind the conical washer. Very impressive performance. Both motors run in sync and the buckets open and close very quickly.

Do you know of anyone using this configuration and any long term issues doing this?

Thank you for doing all the investigation work. It really helped.

Jeff Schroeder

[Richard M.]

Jeff,

It shouldn't be a problem but on later units I kept the factory configuration. To do this I ended up shaving the gears on my lathe to eliminate the problem.

Others have used a grinder to reduce the flat washer thickness.

My thoughts are that the gearcases have shrunk over time and the result has tightened up the original tolerances. I admit no proof though. It's still a mystery to me.

Rich