Fix your reluctant electric windows

Eunos Roadster "Slow" Power Windows fix

The power windows of my Eunos have from the very first year been a great disappointment as they were slow in winding either up or down. Since the whine of the motors was quite alarming, I tried lubricating the window tracks and cable capstans a few times, using all sorts of lubricants including graphite grease (absolute crap as it blackens everything and slows the windows down even more) to no avail, as they could only temporarily alleviate the problem or worsen it (in the case of graphite grease).

Therefore, last weekend I decided to try and remove the glass from
the regulator assembly in order to see whether there was anything
obstructing the window guides. The procedure is simple and is performed
as follows:

  1. Remove the door pull by unscrewing the three screws (two at the
    bottom and one at the top of the door pull, concealed under a plastic
    cap, which needs to be removed using a flat screwdriver.
    2. Slide
    the door lock knob to the “lock” position, unscrew the screw found
    underneath it with a Phillips head screwdriver and remove the door lock
    3. Remove the door panel by gently pulling on the edges of the
    vinyl-covered interior board until the clips snap off the door shell.
    Once you are done with the door clips, carefully lift the door panel
    upwards and away, releasing it from the door shell. For those with
    tweeters mounted on the door panels, do not yank the panel off, as it
    may sever the wire harness. Disconnect the tweeter wires.
    4. Slowly
    and carefully remove the nylon that seals the door shell, being careful
    not to get any of the black gunk onto your hands or clothes. The thing
    never dries up, is impossible to clean off clothes, and once you get it
    onto your hands you must go through all sorts of improvised (and thus
    painful) cleaning procedures only short of chopping your hands off for
    convenience. Depending on the spec package of your Miata, you might have
    to remove some hardware to avoid ripping the nylon apart (i.e. the
    inside door lock mechanism, power door lock actuators). Once the nylon
    is removed, you should have access to the innards of the door shell, and
    regulator assembly.
    5. Looking at the side of the door, where the
    lock mechanism that latches onto the car frame is (it is the same
    location that the tire pressure sticker is situated) you will see a
    small black plastic clip at the top that fastens the edge of the plastic
    window weather-stripping onto the door. Carefully pry that off using a
    flat screwdriver and pliers and then gently pull the weather-stripping
    up and away from the door, taking care not to break any of the remaining
    plastic clips that fasten it to the door.
    6. Turn the ignition key
    to start, and wind the window down about 1/3 of the way, to reveal the
    three screws that attach the glass to the regulator assembly. Unscrew
    all three using a Phillips head screwdriver or a 10mm socket wrench in
    case they are too tight (you may need to move the window up or down to
    enable you to unscrew all three).
    7. Wind the window down halfway,
    and unscrew both window stops (these are the white round capstans
    attached to the glass on either side of the forward power window track).
    You are now ready to remove the door glass from the door.
    8. Whilst
    holding on to the glass firmly (remember you are about to remove the
    thing don’t let go of it otherwise it might fall out of the window
    tracks and break) tilt it a bit to the back (pull the rear side of the
    glass up and rearwards whilst winding the window up to remove its
    forward edge from the front window frame) and carefully wind it up all
    the way and lift it out of the door shell.
    9. Have a good look at
    the tracks to see if there are any visible obstructions in the tracks
    (in my case there were a couple of mashed leaves and the remains of a
    rather unfortunate lizard (!!!) caught in there). If you cannot see
    anything, then try and feel the tracks for any obstructions using your
    fingers. Once the tracks are cleaned, you can apply a bit of lithium
    grease to the tracks and cable capstans, a process that is much easier
    now that the glass is gone.
    10. Check that the rear white Teflon
    guide (this guide goes into the rear window track) attached to the
    window is not damaged, broken or disfigured. In my case (on both doors)
    the rear guide was disfigured (i.e. it was warped and looked more like a
    crooked donut than a flat disc as I am sure it looked like when
    installed at the factory 6 years ago). There are two choices available
    to repair the problem. The first one entails going down to your local
    Mazda dealership and making them richer by buying two new rear window
    guides and replacing them (a rather cumbersome procedure) or reuse the
    old ones after, of course, performing a bit of “cosmetic surgery” to
    them. Replacing the window guide is rather cumbersome and entails taking
    a risk of breaking the glass if the right precautions are not taken.
    For those who never chose the easy way out in their lives: First, the
    glass around the window guide where you will be working, should be
    covered with some army tape to prevent it from being scratched in case
    your pliers slide off the rear washer whilst holding it fast. Next, the
    rear washer should be sprayed with some penetrating oil to loosen the
    bolt, which will almost certainly have seized from dirt and exposure to
    the elements. After allowing the penetrating oil to take effect, use
    safety pin removal pliers (insert the two tips of the pliers into the
    holes on the washer) to hold the washer onto the back of the window
    guide, whilst using a star wrench (T40) to unscrew the bolt. Make sure
    your movements are slow and precise as any mistake could cause the glass
    to crack or shatter. Once the bolt has been removed, replace the window
    guide and reassemble in reverse order. Ensure that the bolt is not
    overtightened as this will most certainly break the glass.
    12. The
    simplest, cheapest and most effective solution in my opinion is the one I
    have chosen to adopt, which was to perform some “cosmetic surgery” to
    my disfigured window guides. This will work ONLY if your window guides
    are not cracked or broken. Looking at the top of the window guide, you
    will see a narrow raised ring on either side, which I presume is for
    eliminating any play in the window guide/track assembly. Since my window
    guide was not so disfigured or cracked in any way to render it
    unusable, I decided to “carve” the raised ring off both faces of the
    guide, thereby smoothing the surface and making the guide thinner, to
    enable it to move with less friction in the window track. This was done
    using a sharp blade, and there was no need to remove the window guide
    from the glass.
    13. After the fix is performed, the window is
    reassembled in the reverse way to disassembly. In order to make you
    windows wind up and down faster, once the glass is mounted onto the
    regulator assembly, loosen the bolts (not too much, just enough to allow
    the assembly to move) that hold the regulator assembly onto the door
    shell as well as the bolts that hold the rear window track onto the door
    shell. Lower the window halfway down, and tighten the bolts of the
    assemblies that you loosened before in the place where the window pushes
    them after ensuring that the window is running straight in its guides. I
    have tried tightening the bolts in different positions, including the
    position where the window was wound fully up, but found that adjusting
    the regulator in the middle position allows the glass to move more
    14. Finally, replace the door shell nylon, the door panel and door pull in reverse order to disassembly.
    Repeat the procedure for the passenger side window. It is worth
    mentioning that the passenger side window guide was warped exactly like
    the driver side.