88 Headlight Motor Shaft Separation (Page 1/1)
88Fingers SEP 29, 11:47 AM
Hey Guys, '88 GT, redoing the Drivers Side headlight motor pins and found the actual issue was that the actuator shaft has separated from the rotor where the pins go. It looks like it was shrunk fit? Any known fix for this or am I ordering a new motor? Thanks for any suggestions guys and gals.
olejoedad SEP 29, 12:33 PM
I have encountered this as well.
It was a headscratcher for a while!
I had a spare shaft, but I suspect it could be drilled and pinned, staked, silver soldered or even bonded with the proper adhesive.
fierofool SEP 29, 01:43 PM
Some folks here have drilled and pinned the housing to the shaft, but I think that could weaken both, creating a breaking point. I don't know what it would cost to have a machine shop do the job, but when I was in a shop, we would metalize a shaft that had been galled. It's a process of spraying metal particles through a flame as the shaft is rotated. Then the shaft is turned down to the desired diameter.

The original shaft and housing were probably shrunk fit, as you surmised. Maybe the shaft was chilled and the housing was heated then assembled. You might be able to get some Red LocTite Threadlocker. It's the strongest of that brand and requires heat to separate the pieces. Just be sure you have the housing at the proper depth on the shaft and let it cure for a full day.
88Fingers SEP 29, 02:30 PM
Thanks for the input guys. I am thinking drill and tap the rotor for a set screw I could loctite? This may hold it strong enough for just the few times I use the the headlights which is not that often. It looks like new motor from TFS then if all else fails? $125 USD for me here in Canada. LOL! .....Fred W
olejoedad SEP 29, 02:48 PM
File a flat spot on the shaft to land the setscrew, Loctite the setscrew and you shouldn't ever need to revisit the repair.
Mike in Sydney SEP 30, 05:46 AM
Same problem here, too. I tried multiple ways to fix it and was never satisfied. The gear on the shaft always slipped. Occasionally you can find used shafts on ebay but I broke down and bought two new motor from summit. Problem solved but is was pricey - about USD $100 per side.

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Mike in Sydney

theogre SEP 30, 09:54 AM
if "pins" look new then very likely mean someone put Delrin pins in and why you now have blown output shaft. Has that or gear breaks. Like gear(s) have some damage teeth.
See http://www.fiero.nl/forum/Forum2/HTML/128600.html

Fixing output shaft then motor etc often only fails again to just break next "weak" part.
Some will happily sell you metal gear but does same thing.

get new motors.
Cheap ones from Ebay etc have very limited or no warranty
AZ, Cardone and some others are more expensive but have lifetime warranty.

After getting new motor(s)...
Use a light bulb like spare 194 or small small bulbs drawing less amps as possible and wired to back probe motor connection to watch module turns off instantly at motor's End of Travel.
If not and turns of after ~5 sec then module has problems too because can't see motor is stalled at EoT.
See my Cave, Gen 2 HL Motor

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

[This message has been edited by theogre (edited 09-30-2019).]