TheExaminer

I just rebuilt my headlight motors today, it was my first HM rebuild. Reinstalled the motors and they work fine, but there's an issue I need tips on. When I first opened them after rebuild, they were haphazard. One time both would open, next time one would, then they would open and close, but not open again. After a few minutes of experimentation. I found the problem but am not sure what caused it or what to do. The motors have too much travel when closing, which binds them up for the next cycle. If I turn the ***** 1/4 turn open to losen them up, they open the rest of the way fine when you hit the button. Then they close fine, but won't open next cycle unless you do the 1/4 turn. Did I not get the gear shims back on in the right order and place? I tried to keep track of what went where, but maybe I missed something. If I did, how am I going to know which shims to move where? Both motors are redone, I have no point of reference anymore. Btw, ball bearings at the tips of the worm gear were reinstalled, so no issue there. I've also noticed the pass side opens a little faster than the driver's side. Not sure what's up with that either.

TheExaminer

One more thing....one screw on each motor housing sheared off when I opened them (not gear, but one of the two on the motor housing). I did not tap them out and replace them yet because I don't have the right drill bit now. I installed the other screw and was going to tap them out and put new screws in later. Not sure if that's part of the issue. Could be, but I don't see how.

OrangeBird

iTrader: (1)

The broken screw is a perfect reason for the problem because when the motor spins in the direction that would put rearward force on the armature , it will over travel in the amount that it pushes the unbolted side of the motor away from the gearbox housing . Obviously the direction that puts rearward force on the armature is the down direction since it over travels then and won't come back up till ya "un over travel" it by spinning in the up direction 1/4 turn to get it unbound .

Short answer = Fix the screw

TheExaminer

Ok, sounds simple. I'll tap them out and put in a new screw Monday when I have a chance to get to Lowes and get a tap. Thx. Hopefully that will do it!

lonsal

iTrader: (2)

The screw should be replaced I agree. I include two screws and nuts with the TDS 209280 deluxe headlight repair kit I sell just for this reason. The screws I supply are slightly longer than the OEM. I recommend using a clearance drill and using the nut on the back side. Just grind the remaining screw flush, then use a center punch to locate the hole and drill all the way thru. It is far easier to do this than trying to drill and re-tap. But if it is more important to keep the original look then drill and re-tap.

The reason why your headlight is binding is that the small ball bearing on the end of the worm-drive shaft is either missing or is not being supported by the small stub-shaft on the opposite side of the worm-drive shaft.

The ball bearing is supposed to hold the end of the worm drive shaft. If it is not there then the worm-drive can climb the OD of the large plastic gear and jamb.

To fix it carefully pull out the worm-drive and verify that the small ball bearing is in the cup on the end of the shaft. It should be attached with a dab of grease. I sell spare ball bearings if you can't find yours. If it is there, then reassemble the worm-drive shaft. Next use a flat-blade screwdriver to hold the end of the stub-shaft in place then loosen the sheet metal nut. Then tighten the stub-shaft until you feel a bit of resistance. Tighten the sheet metal lock nut.

Lon Salgren

TheExaminer

I have the kit with the longer screws. I just mean I'm going to drill it out and use the nut--wrong terminology I guess..... I made sure the ball bearings were in place. When you said stub shaft I didn't know what you meant, but now I remember. It's the shaft at the opposite end of the worm gear that protrudes from the bottom of the motor. Got you now....It could also be that the worm gear and ball are not fully set because the housing isn't screwed all the way down where the missing screw is. There is a slight separation between the two right now. Putting in the new screws will probably fix this, but if not it will be pretty easy to check to see if the ball bearings fell loose, or to adjust that stub shaft. In fact, seems to me it would be easier to just open the plastic gear housing and pull it out to check the end of the worm gear so you don't have to mess with holding the brushes back to reinsert the worm gear if it turned out the bearings were where they were supposed to be.

lonsal

iTrader: (2)

Just be careful with the brushes (specifically the braided copper wire attached to them) when you retract them.

Good luck with the repair.

Lon

TheExaminer

Yes, I used paper clips the first time, and wasn't crazy about it. If I have to pull them again, I'm going to use string or fishing line.

TheExaminer

SUCCESS! Drilled out the old screws, put in new, made a slight adjustment on the stub shaft and they work just like new!

OrangeBird

iTrader: (1)

That's Great ! Nice to hear a success story every now and then .

lonsal

iTrader: (2)

I'm glad you had success. It took me a while to figure out what was causing the motor to jamb after being repaired. It finally dawned on me that the end of the worm drive was not being properly supported by the ball bearing and stub shaft. As a result the worm drive was free to climb the OD of the gear and jamb.

Again I'm glad you had success in the repair.

Lon Salgren

TheExaminer

Thx. I did screw up one thing though. After I had to take the motors apart the second time yesterday, I got everything installed in the car and came back inside to find a couple shims laying on the table. @&#%! The good thing is, I'm pretty sure they're the ones the go between the plastic gear and gear housing cover on the rh motor and they dropped out when I took the cover off. If so, I should be able to take the cover off and put them in without removing the whole thing again.

TheExaminer

No dice. Had to take the assembly out again anyway, just too hard to take the cover off with it in the car. But, got it done in a few minutes, shims back in place. I think the gear might have run out a little because it was a little slower opening the first time I put it back together, but I think it seated because every time after it opened right with the LH motor. So no harm done I guess, working great now.

TheExaminer

BTW Lon, thx for the rebuild kit. Good, solid instructions--easy to figure out and follow. Anyone could do the job using this kit, I'd recommend it.