RH Headlight Motor Gear Replacement.
 

This may or may not have been posted recently.
I just finished up with the job and thought I would post my experience with changing the plastic gear in the headlight motor.

Yesterday while showing off the car to some company, after lowering the headlights I noted a strange noise. I turned the headlights back on and once they came up to a full stop the noise quit. I lowered them and once fully down the noise continued. I popped the hood and found the right side headlight motor was running continiously. I turned the headlights on again and once they opened up, I moved the switch to the parking light position and disconnected the battery.

After some debate and a couple of phone calls, I found the part at "Corvette Country" in Fayetteville. All he had was the plastic gear, but it was better than nothing and I did not want to wait a week to get the brass gear.

The replacement should be good for the '97 to 2000 models. I think in 2001 the motors were "sealed".

I tackled the job this morning and it was pretty easy. It took me about 1.5 hours start to finish.


Tools I used -
1.4" ratchet.
3/8" ratchet.
10 mm sockets for each ratchet.
10 mm combo wrench.
1/4" drive, 1/4" socket.
Phillips screwdriver.
#15 Torx.
5/16" "dogbone" wrench for the battery connection.

With the headlights up and the battery disconnected I removed the plastic bezel from around the right headlight. This is held on by three phillips screws.

http://img301.imageshack.us/img301/5...60019dm.th.jpg

I removed the "Lid" for the right headlight by removing the four (4) #15 Torx screws. There are two in the back, one on the right side and one on the left side. Notice these have slotted holes. This is how you can adjust the lid so it is flush with the hood, fender and front bumper.

http://img127.imageshack.us/img127/8...60032py.th.jpg

Notice the position of the headlight actuation arm and which direction the elbow bends. Taking note of which way the elbow bends when closing the headlight with the manual knob will save some headaches a little later.

http://img127.imageshack.us/img127/8...60048rm.th.jpg

The headlight actuation arm is held on by one 10mm nut.
The headlight motor is held on at three attach points, two of which are 10mm bolts and the last one (upper aft) is a 10mm bolt that runs through the unit and frame and secured with a 10mm nut.
In the picture you should notice the ratchet on the right (inboard) side of the motor, and a 10mm wrench on the left (outboard) side of the motor. The combo wrench is holding the nut.
NOTE: Once the actuation arm is free from the drive shaft, the headlight assy is free to move to the retracted position.

http://img301.imageshack.us/img301/4...60075jj.th.jpg

Once the three attach points and the actuation arm hardware has been removed, the motor can be worked free. There is still a harness connected. I opted not to disconnect the harness.

http://img437.imageshack.us/img437/9...60101vy.th.jpg

The gear cover is held on by three 1/4" bolts. Once you remove these bolts make sure you remove the gasket as it will be replaced. As you remove the cover, note on the drive shaft there is a washer, then a plastic spacer. Remove these and keep in a safe place. BEFORE you remove the drive shaft and plastic gear, make a reference mark on the drive shaft and the housing. This is important so as to relocate the drive shaft in the same position. The opposite end of the drive shaft where it connects to the actuation arm can be connected two ways.
Once you remove the drive shaft and plastic gear, note there is a plastic spacer and a washer on the other side of the plastic gear.

http://img389.imageshack.us/img389/7...60120ow.th.jpg

Here is the plastic gear, drive shaft, plastic spacer and washer.
Pull the drive shaft from the plastic gear and replace the gear. The gear has "slots" and the drive shaft has "ears" which will engage easily. I applied a light coat of plastic grease to the gear teeth.

http://img389.imageshack.us/img389/3...60155cz.th.jpg

Here at about the six o'clock position you can see the damage to the gear itself and the teeth which caused the motor to run continiously.

http://img389.imageshack.us/img389/9...60171uv.th.jpg

Reverse the removal / disconnect procedures and use the reference marks on the drive shaft and the housing made earlier to reassemble everything.

Nice write up. I wish the pictures were larger though.

click on them.

I have. They don't enlarge for some reason.

Good write up and lessons learned. Yeah, the motor covers on my 2003 were sealed and I obviously didn't do a very good job sealing them up. I'm having trouble with the motors since the covers are cracked open, and they appear to have worked loose from the mounting. But the brass gears are still doing fine. It's a shame Chevy was so cheap with the headlights.....

Yep. I had the same problem on my C4 as well.

I changed my PS headlight gear to brass about 3 weeks ago. On reassembly, I used liberal amounts of epoxy to reseal only to have the cover pop two days ago. Now, headlight won't raise.

I'm going to try using the method I read, where small holes are drilled on the perimeter and eyeglass-size screws are utilized to hold things (hopefully) permanently.

can this be done without pulling out the motor??

cool...did it real easy. Opened up the headlight by hand...took off the three screws on the motor..snaked a small wrench around the back..undid the arm nut..pulled out old gear..stuck on new..closed it back up. Took about 20 minutes..lol. Didnt move the headlight motor at all...worst part was the wrenching of the three motor side screws. peace

A quick, easy, and free fix for this problem is simple. Raise the headlight, turn switch back to running lights. Remove the 10mm nut holding the control arm to the motor, carefully work the control arm off of the shaft.. Put a reference mark on the shaft, then use the manual knob to rotate the shaft 180 degrees. Reinstall the control arm and nut. You are now using the oposite 1/2 of the gear teeth, get ya down the road for a few more years.

That sounds simple enough. What I'm not clear on why raise the head lamp, then switch it back to the running lights? I assume the lamps will close when you swich it to the running lights.

FYI - some have commented that only 1/2 of the plastic gear is used so you can do the above procedure to use the other 1/2.

However more than 1/2 of the gear is used, more like 2/3 of it is used which is evident when you look at the positions of the open and close stops on the headlight assembly.

I tried the above procedure and found that the bad spot on the gear was now hitting when the headlight was about 80% raised and the bad spot was stripped enough that it was preventing the headlight from fully raising. It may buy you some time to do this if you're gear is not badly stripped, but it's only temporary.

Bubbletop409 must have been a Trans Am owner at some point, as that trick works on the 93 to 02 TA's.

Yea, ditto here. I tried that as a quick fix while I was waiting on my brass gears to come in the mail and all it did was change the place where it made the noise from the down position to the fully raised position.

I have a question.

I have a 1999 C5 with 40,000 miles and the original headlight gears are still fine.

How soon do you think my gears will go bad ??

Or should I ask ... When do these gears start to go bad ??

I'm sure the time is going to vary from car to car but about when do you think they are going to fail ??

I'd just like to replace them before they go bad.

Shhhhhh......just click away and pretend like you were never here. You don't want to jinx anything. :D




Seriously though, you can never tell. If yours were the newer type that have to be epoxied back together, I would tell you to leave them alone, but since yours are the bolted style, I say do it. Less than $100 and you never have to worry about it again.

Thanks, will do.