Hideaway Headlight Motor Rebuild

[tsmithae]

Alright, if your motor doesn't work well or will only go one direction, there are a number of reasons why.  However, if you have narrowed it down to the motor and are feeling ambitious (as I was) then here is a little write-up on how I did my motor rebuild.  Hope it helps!



To start, the motor was missing one of the leads from the switch to the coils on the motor and the lower bearing was frozen. 





First, I removed the plastic cover that housed the switches, gear (white), and cam (red).  You want to turn the motor (if possible) to the point where the notch on the drive gear and the cover line up (this is the halfway open/closed position).






At this point in time, inspect your gear (if you need one, contact Topher! http://1970chargerregistry.com/mboard/index.php?topic=57.0), cam, and switches for wear and breakage. Also, check that your switches are both making contact in the halfway position, if not, adjust them accordingly so that they are contacting and that they are only losing contact when the gear has reached full travel in that direction.





Next remove the 2 long screws that are located at the bottom of the motor (under the thumbwheel, which will need to be carefully pulled off as it it plastic and NOT threaded, it is merely a pressed fit) and pull the bottom plate out only enough so the brushes are visable. You will want to use a small screwdriver and pry open the back of the spring retainers in order to remove the springs.





Next, if your bearing is frozen as mine was, grab your 3-jaw puller or something similar to push the rotor, this will actually remove the bearing from its seat so don't be alarmed.  Once you have accomplished that, your rotor will be free to come out the top of the case and you will want to remove the brushes from their retainers.  I took this opportunity to clean the contacts on the rotor where the brushes ride.  Also, you will want to do a continuity test on your stator coils and your rotor as well.  The contacts on the rotor should all pass continuity but should not be passing continuity to anything else.  The rotor coils should not pass any continuity.  The stator coils should have continuity from one terminal on the pigtail all the way to one brush and nothing else.  If there is no continuity, check that your switches are in contact and that your leads to the stator coils have solid solder connections.  If there are any shorts in either the rotor or the stator, commence your search for another motor (which was the same throughout the 70's for mopars).






Now, for the broken lead.  I removed both leads (copper to female, dark to male on the pigtail) so that I could get fresh solder on both and ensure a good solid connection.   After the solder had cooled, I applied liquid electric tape to seal it; I also applied some to the pigtail solder points as they had begun to poke through.






Now, this was the most difficult part... which is probably the reason I forgot to take pictures during it...

However, press the bearing off of the rotor shaft and clean both up using fine sandpaper, ensure that the shaft moves freely within the bearing before reinstalling. 

Next, you will either have to remove the fiberboard that the brush retainers are attached to or cut out a portion of it on one side.  Then, remove the bearing retainer, replace the bearing, and work the retainer back in place, starting with one side and working around in a circular pattern until it is FULLY seated,

Reassembly is easy and just the reverse of disassembly, replace brushes, replace the rotor in the case, seat the bottom plate then the top plate, tighten 2 long screws, insert gear in the halfway position (it appeared that the factory had used white lithium grease so I did as well), insert the cam, ensure your contacts are in the halfway position as well and put the plastic cover/retainer back in place  and replace the 5 small screws.



Numbers





Finished product

[b5blue]

Awesome... ..Now I have a fighting chance of saving my original motor with the new gear set from you. Thanks! 

[Iron Chef]

Great write up.  I don't have a Charger with Hideaway Lights, but these types of write ups with pics are super helpful!