While attempting to remove a seized nut that attaches the actuating arm to the motor I managed to strip the gear that raises/lowers the headlamp bar so the lights would only go up half way and then the bar motor would start slipping. Rather than scrap the motor I repaired the gear as follows (this applies to on OB car BTW)

1) Start by removing the motor from the car by undoing the nut that holds the actuating arm. Make sure you counterhold the arm when doing this otherwise the spindle will spin with the nut and this is what damaged my gear. After that undo the three M6 bolts that surround the spindle and lift the motor out after undoing the 4 spade connectors. They are numbered 1-4 so make note of which wire connects to which pin.




2) with the motor out of the car, peel back the rubber sleeve. You will find that it cant be completely removed without cutting off the wire harness. However you dont need to do this you just need to expose the 5 flat head screws which hold the gear cover in place. undo the screws and remove the cover, the gear then simply pushes out however take care not to lose the ball bearing that sits in the centre of the gear (if you do its a standard 3mm bearing widely available) or the washer that goes on the spindle.




3) here is what the stripped gear looked like!




4) To repair it start by coating all the gear teeth with a 2 part steel repair epoxy. I used some JB weld which I had lying around.





5) this is the delicate part; you need to wait until the epoxy is semi dry, when it is still soft but lost its tackiness. I waited 6 hours based on a 50/50 mix of epoxy & hardener but times will very depending on the type of epoxy and the amount of hardener. coat the part that the gear engages with silicone grease to prevent the epoxy from sticking to it and then refit the gear into the casing. Use the manual dial at the top of the motor to turn the gear 1 or 2 full revolution. This will cut new teeth into the epoxy.





6) Remove the gear carefully and allow it to fully cure. I left it for 2 days. I then trimmed and sanded any excess epoxy using a minitool before refitting. refitting is the reverse of removal. The sleeve is rather fiddly to refit but dipping it in hot water for a few minutes helped as did using a screwdriver to lever it over the spindle.





7) Job done. Hopefully motor should work again.

 

Nice idea. I will be interested to hear how durable it is. Very clever.
Thanks,
Dave