84-86 Headlight Motor "Glass Tube Breaker" Inquiry (Page 1/1)
glwalker04 AUG 15, 10:45 AM
Hello,

I am looking for anybody who has any information about the little glass tube circuit breaker in the switch of the motors for the 84-86 model years. I assume this is a circuit breaker at least. Thought it might be heat operated and I melted mine when testing my motors a while back. I am wondering mostly if anybody has any info on the electrical specifications of it or where to get a new one . I rebuilt my right hand motor and got it to work flawlessly, the lefthand one is the one I suspect has a fuze issue and was originally working but no longer is. I will show a picture of what mine looks like but I determined the brushes and all other mechanisms of the motor/switch are in working order, in a previous owner had at one point used a rebuild kit on it aince it has the non-factory bolts. I would like to revive this motor since I know it can work. Below will be pictures of a clean "new" breaker versus what mine looks like.

Clean:


Mine:
theogre AUG 15, 12:54 PM
It is an auto reset thermal breaker.
Likely a small unit as runs @ 3-4a in normal use but also won't "trip" @ End Of Travel or Jam doors that pulls more amps just before the limit switches open.

If you breaker Fries... then Winding of the motor likely Fried too. You likely need another armature.

------------------
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

cvxjet AUG 15, 03:32 PM
I rebuilt my 85 motors....But still had some issues.....Then my battery went dead a couple of times. Realized that these old motors work flawlessly until they are old...approx' 30 years...Then they start having issues with running on.

I was testing the motors on the car...Heard a noise as I was leaving the garage- started looking around and happened to touch the left-hand motor>>HOT!!<< I was able to unplug it...later I was showing a friend what had happened- Had NOT turned the lights/motors on...Heard a noise again and went over and checked the right motor- It was at 160*! I had not turned them on in 2 days....It was just sitting there and decided to start going.

A few people have lost Fieros due to fires caused by the first-gen motor...You can get an 87-88 front light harness and controller (Under left front fender), install it and then purchase NEW 87-88 motors...The new system has a "Time-out" set-up that simply shuts it off until you flip the switch again- much safer.

[This message has been edited by cvxjet (edited 08-15-2023).]

Dennis LaGrua AUG 17, 04:12 PM
IMO, the gen 1 headlight motors are not hard to rebuild but often do not function 100% or provide long life. If the circuit breaker was cooked check the rotor windings before rebuilding but even if they check out there is no replacement available to provide internal overload protection. I guess you could solder in a 15A glass fuse in as protection. General wear and tear can wear to the gear and the switches make rebuild questionable and increases the possibility of sticking.
I have had great success with Rodney's rebuild kits and the motors on my 85GT seem to work flawless but as stuck motors can cause a fire I installed a main headlight power cutoff switch when parking or in the garage.. IIRC it is the white wire on the harness.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

buddycraigg AUG 24, 11:48 PM

quote
Originally posted by glwalker04:
Mine:



I have never seen the circuit breaker go bad, no matter how bad it looked.
Have you tested it for continuity?


quote
Originally posted by cvxjet:
A few people have lost Fieros due to fires caused by the first-gen motor...



I do not believe you.
theogre AUG 25, 10:40 PM

quote
Originally posted by buddycraigg:
I have never seen the circuit breaker go bad, no matter how bad it looked.

I have. More so when whatever makes the auto reset types to cycle a lot like common fail w/ Gen1 killing the battery.

Most Breakers of Any Type Are Not Switches to run whatever and have a short life when repeatedly tripped or turn off under load.
Related Example: People using Breakers to Turn On/Off 120/230VAC for shops etc then wonder why they have to replace cooked breaker often. Worse when a breaker used as a switch burn and heat damages other breakers or even the load center.

If the "fog" is on Inside of glass...
Most of this type have Air in them and arcing burns the contacts then Soot/"fog" the glass. (Contacts can burn in Vacuum but often cause "mirroring" the glass.)
If Tripped a lot then even the Glass get hot and fails to protect after. You may not see a crack but micro cracks can let air and crap in it.
buddycraigg AUG 26, 04:49 AM
Okay,
maybe you have seen it, but I have not.
fierofool AUG 26, 09:26 AM

quote
Originally posted by buddycraigg:


I do not believe you.



I loaned one of my cars out to a club member. The right headlight motor malfunctioned and caught fire enough that the motor started to melt. Fortunately, it extinguished itself. There also was a video floating around Pennocks of Fiero fires. One scene showed a Fiero sitting in a parking lot with the right headlight afire. Destroyed the car before the fire department arrived. There's nothing else in that corner of the car that could cause it. The fireman couldn't find the hood latch so he pried open the headlight door.
https://www.youtube.com/watch?v=2hEax-qFUuY

fierofool AUG 26, 09:32 AM

quote
Originally posted by buddycraigg:


I do not believe you.



I loaned one of my cars out to a club member. The right headlight motor malfunctioned and caught fire enough that the motor started to melt. Fortunately, it extinguished itself. There also was a video floating around Pennocks of Fiero fires. One scene showed a Fiero sitting in a parking lot with the right headlight afire. Destroyed the car before the fire department arrived. There's nothing else in that corner of the car that could cause it. The fireman couldn't find the hood latch so he pried open the headlight door.
https://www.youtube.com/watch?v=2hEax-qFUuY

theogre AUG 26, 03:50 PM
Gen2 motors & module can melt down to start a fire too but often that's because someone tried the "fix" the Module and Failed.
Including Cliff P @ https://www.fiero.nl/forum/...14-2-095675.html#p29