First problem is getting the riser out. As complicated as the
instructions on the web are, I found it even harder. I ended up knocking
out seven pop rivets and unbolting the rear window channel. I have
a bigger photo linked to the above thumbnail that you should look at.
I had to remove the five motor mount rivets as well as loosening the cross
bar and swiveling it out of the way, and the top power lock bracket rivet.
See what's circled in the bigger photo.
Even after that, I had to have an act of congress to get the motor
past the lock solenoid.
You need to fix the window so that it doesn't fall down. I used
C-clamps and rags on the edges of the window glass to hold the window up.
I'm told that another good way is to use duct tape where the window comes
out of the door.
To get the BIG pop rivets out, grind the top flush with the head, THEN
hit the center with a punch. It should pop right out.
Oh yea, nobody mentioned it, but there is a connector at the base of
the motor. It is locked in by a long press bar that's at the bottom
of the assembly. I ended up cutting my wires, and didn't need to.
The unit looks like this, pardon the shadows, but it was about 100
out when I did this, so I was looking' for shade.
I could run the riser motor out of the car, and verified that the motor
would run the riser up and down, but would skip when it got to a certain
point. This verified that there was a problem with the gear train.
If there was ever an inseparable assembly, THIS is it. But, I
figured I should try to fix it if I could, so onward into the assembly!
Here's the assembly, disassembled. I had to grind and drill about
10 rivets and folds to get it apart. What I found is that the black
gear near the center of the photo had lost a couple of teeth, probably
because it was near the top or bottom of the action. It effected
the action about three times in a cycle - top, middle, and bottom.
I did what I could to repair the assembly. I rebuilt the missing
teeth on the black gear with epoxy, then ground them and reassembled the
motor. When I reassembled it, it whined like a mechanical alarm!
I just wasn't going to be able to fix the motor assembly.
I did find though, that you can remove the plastic brush holder (far
left of the photo) from the unit by bending three tabs on the bottom of
the motor. If your unit has quit and you've verified that it's not
an electric circuitry problem, it might be worth it to remove the riser
and remove the brush holder and check the brushes, they could probably
be replaced with a little work and luck.
Next thing was to look for a replacement motor. I did some searches
on the web, and found that the motor unit assembly was an aftermarket part!
I found this unit IN STOCK at my local AutoZone store new for $50.
Obviously, the unit is a standard part for many GM cars. The included
bracket is not used in this application.
Onward to installing the riser from my old motor.
Here's photos of the riser removed from my old unit. A couple
of hints are to MARK the relation of the motor bracket and the gear arm.
It will make the assembly back into the door easier. Before you remove
the riser from the old motor, also remove the big spiral spring.
Mark the direction of spring spiral onto the riser so you get it back on
the right way. BE REAL CAREFUL with the spring. It's big and
could easily bite you.
Here's the reassembled power window riser unit. I used small
nuts and bolts in place of the original rivets. Three rivets hold
the window riser and two hold the small bracket on the end of the motor.
If I'd had the right size pop rivets, they probably would have worked too.
Now all you have to do is reassemble the unit back into the door. You already know how if you took it apart. I could only get to the back of three of the five mounting points to install bolts with nuts. There was a very good hint somewhere about using large self-tapping screws and then grinding the ends off after you've gotten them to start their own threads. I'd do that if I had had the screws. Meanwhile, I'll see if it works this way.
Door is back together, the window goes up and down, and it's ready
for a good cleaning. One more Fiero mystery exposed. If anybody
has additional info, I'd like to add it. Just send me your comments!
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