Inaccessible torx screw for window lift motor with stuck motor/regulator (1 Viewer)

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First time for everything I guess. Left rear window not working, motor/regulator stuck in the full up position. Got power to the switch and switch working, pushing the door switch all I get is a click coming from the motor.

Removed the four bolts holding the regulator to the door and it swunge loose (taped the window to the door first so it wouldn't fall), then slipped the regulator rearward out of the single channel the roller wheel slides in.

So I have the regulator on the table, using a Milwaukee Fuel cordless compact drill driver/impact with a T25 Torx bit and zziipp-zzipp removed two of the torx screws.

Here's the problem, can't get to the third screw, the regulator arm is directly over that one remaining screw and the arm won't budge.

Does the Mud hive mind have a solution?

FZJ80 Rear window lift motor and regulator stuck closed.jpg




FZJ80 Rear window lift motor inaccessible torx screw circled red.jpg
 
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Considered drilling a hole, but wanted to see what other options were out there.

As I recall there is just a small post/shaft under the cover once the gear is removed, might try that.
 
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LandLocked93

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The hole you see in that arm provides access to that screw. Plug the motor back in the door and use the window button to line the two up.
Release the spring pressure before removing the motor. And be sure to return the arm teeth - to the position they were in when motor was removed - before remounting the motor.
 
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Landlocked: Thanks for the suggestions but the factory hole does not line up with any of the Torx screws, and the motor was frozen, so couldn't move the postion on the regulator. There is no spring, this is a rear door regulator

Shipwreck and Spike:
Tried your suggestions: first powered the motor directly from a 12 volt battery, no movement, no click, dead (I did however set off the factory alarm on my 97 when I connected up the wires to the battery).

Then took the motor cover off by prying on the little metal tabs. Found rust (cover looked poorly sealed from the factory allowing water to get inside). Then removed the small Circlip holding the plastic gear and pinion together and pried the gear out. I could easily then turn the armature using vice grips and move the position of the regulator arm to get to the Torx screw, zzipp and done.

Photos below:

Rear window lift motor internal rust.jpg


Rear window lift motor cover removed.jpg


Rear window lift motor stuck turning pinion with vice grips.jpg


FWIW: the Milwaukee M12 impact driver in the middle photo above is a great tool for jobs like this, beats turning a wrench for removal of fasteners.
 
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Landlocked: Thanks for the suggestions but the factory hole does not line up with any of the Torx screws, and the motor was frozen, so couldn't move the postion on the regulator. There is no spring, this is a rear door regulator

Shipwreck and Spike:
Tried your suggestions:

.... took the motor cover off.... I could easily then turn the armature using vice grips and move the position of the regulator arm to get to the Torx screw, zzipp and done.

Glad it worked out.
What's the plan now? Clean and rebuild existing motor / gear or buy a new one?
 
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I pulled the motor apart, found the armature case had also gotten water into it, armature was frozen (by rust) to the magnets, sprayed some Aero Kroil penetrating oil inside the case and gave the armature shaft a few wacks, was then able to pull the armature out.

Sanded off the rust on the armature plates, 800 grit emory paper to clean up the commutator (found very little wear), brushes have plenty of length.

The inside of the case had some rust, but the magnets were still attached
and looked good, no scuffing from the armature (seen that happen when the magnets come loose). The large plastic gear had some of the usual wear to
the teeth.

Cleaned all that up a bit along with the bushings, relubed everything using Dow Corning 33 Medium (Silicone grease with a Lithium base) and swipe of Loctite Moly paste (Lithium base also) for the armature bushings.

Too late to test it tonight, will try again in the am. Will likely
replace it due to the rust even if it works, too much rust inside
the case and I don't want to dig into this again for another 20 years.

Photos to follow.
 
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Cleaned all that up a bit along with the bushings, relubed everything using Dow Corning 33 Medium (Silicone grease with a Lithium base)
I've often wondered what kind of grease to use in these? Is that the right kind or is there better greases for this application?
 
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Dow 33 is a great grease for this application. We use to have snags for pitch trim on the Cessna Caravans up in the arctic. Once we changed out the grease to this stuff in the actuators the problems went away. Data sheet shows -73c to + 180c!
 
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AFAIK multipurpose (petroleum) grease can soften some plastics. The Dow Corning Molykote 33 is compatible with most plastic parts like the white plastic gear that turns the pinion gear in the window lift motor. Also used the DC 33 in the small front seat gearbox when replacing the plastic gear. Despite the brand name Molykote 33 doesn't have any Molybdenum in it.
 
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Here's some more photos showing what I found, appears that the factory rubber seal failed allowing moisture to get inside the case:

FZJ80 rear window lift motor armature case rust.jpg




Close up of the rubber seal: when I install a new lift motor I'll likely
add a swipe of a (?non-hardening) sealant around the base of the case.

FZJ80 rear window lift motor failed seal.jpg


Photo below shows the cleaned up armature and commutator (where the brushes ride) before I buttoned it up:

FZJ80 rear window lift motor cleaned up reassembled.jpg


This one is out of order, shows the rusty armature and case before
I cleaned them. Adding a non-hardening sealant around the base of the case (new or used motor) might be a good idea.

FZJ80 rear window lift motor rusty case armature.jpg
 
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I went out and connected the cleaned up regreased rear window lift motor directly to a 12 volt battery and it's alive!!!! However it sounded a bit growly, was slower compared to another used motor, and much slower than a new motor. IME when they make that growly noise they're close to being done either way.

The motor also shut off in one direction after a few seconds. My guess is too much amp draw which triggered the auto-off circuit that stops the motor when the window closes?? I also wonder how much the DC 33 Medium affected the drag on the motor as I usually use the 33 Light for electric motors like this, but was in a hurry and just grabbed the Medium.

For comparison I tested an original used front window motor (removed due to bent regulator, different thread) and it moved better/faster than the rear cleaned up rusty motor, but both were slower than a new Dorman motor I haven't installed yet.

It was interesting to see if the original (rusty) motor would work after being cleaned up but the old girl just didn't have anything left.

Main thing I learned from this is that the original seals on these motors can allow water/moisture inside and/or humidity from the air gets inside
causing the rust?? I noticed that both original front and rear window lift motors have vents, but the replacement rear Dorman motor does not. FWIW.
 
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LandLocked93

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Dow 33 is a great grease for this application. We use to have snags for pitch trim on the Cessna Caravans up in the arctic. Once we changed out the grease to this stuff in the actuators the problems went away. Data sheet shows -73c to + 180c!
Is this similar to Toyota's 'chassis grease'? (small bottle for $50 or so)
 

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