Rebuilding Convertible Rear Window Motors



Rebuilding Fox Body Window Motors

I had some difficulty recently after buying a window rebuild kit for my rear windows, so I thought I would to a quick write up to cover the rebuild process. I won’t go into removing them from the car, as I hope that if you are capable of rebuilding them, you can manage to get them out. Removal of the front door panel and the rear quarter panel cover are all that is required to access and then remove the mounting bolts.

The window motors in the front of the Fox cars and the ear of the convertibles are different in design but use the same type repair parts in the drive mechanism. Below is a Fox front drive motor followed by one from the rear of a Fox Convertible with the cover removed from the drive.

[pic] [pic]

You can see the convertible has a longer drive shaft because it has a bracket that holds it away from the body.

Once removed, it is obvious that the drive cover screws and bolts must be removed to remove the cover as seen above. When Ford designed these motors, they used a worn gear drive outer gear with three drive pins in it used to engage the output drive gear. This arrangement is the same for both front and rear motors. Ford made the drive pins softer than the worm driven gear so that if the motor was driven against a stop too long, the pins would crush and fail to save the motor. When they crush from wear, you may hear the motor running but the window does not roll up or down – a sure sign the pins and/or the worn driven gear has failed.

Once the cover is off the drive mechanism, you pull the output drive gear up to remove it from a shaft in the center of the gear. This will expose the gear and pins, pull them straight up and out and you will see if the pins or the pins and gear have failed. The pins often grind up so much they are hidden in the grease and the crack in the worm driven gear will be very obvious. I had one set of ground up pins and one cracked worn driven gear.

[pic] [pic]

It’s important that you clean all the grease out of the housing and off the gear so that debris does not another early failure of repair kits. The repair kits consist of just the drive pins or the worn driven gear, the drive pins and sometimes the output drive gear. The range in price was from $6-$10 for pins and $12-$18 for the kit. They can be found on ebay by searching Ford Window Motor Repair. I bought a kit that was advertised for convertible rear windows and the picture used was this:

[pic]

When the kit arrived, the worn driven gear was white, but the drive pins were black. I didn’t think much of it until I went to assemble the drive mechanism. When you assemble the drive, the output gear should be placed on the shaft just far enough to get the new drive pins under the flange on the output gear and above the pocket in the worn driven gear. The pins on mine had one end with a bevel around the end (see pic above) – that end should go down so that when you go to press the pins into the worn driven gear the bevel will help with aligning the “slip-fit”. I had to use a vice to try to press the pins in but no matter what I tried, they would not go in, so I got out my internal snap gauges and micrometer to see what the issues were. The first thing I measure was the pocket width that the drive pins sit in. The pocket was .593” in width – see the below photo. Next was to measure the diameter of the black pins – they measured .533” in width. That means that the clearance for assembly is .060”

[pic]

Now I measured the thickness of the output drive gear where it has to slip between the pins – that was .094” – POW, now I knew why it wouldn’t press together. I had a .033” interference at each pin.

[pic]

I needed a pin that was .500” in diameter to get it together. I called the supplier who did a little dance about how many kits he sold with no issues, but once I sent pictures of what was going on and told him that I had to have .500” pins to make his kit work, he sent them to me. Low and behold when they arrived, they were the color of the pins from the ad and measured .500”.

So, I greased the gears and pins and filled the cavity with synthetic bearing grease. Then push the gear onto the shaft far enough to just slip the drive pins under the gear flange and place any beveled edge on the pin down. I used a vice to press the pins part way in – see below. This picture was taken AFTER I got the pins in. On the rear motors, if you use a vice as a press to get the pins started, you will be forced to stop when the gear gets to the top of the shaft you are pressing it onto as can be seen in the picture below. Once you get here, remove the mechanism from the vice and use light tapping with a tool near the center of the gear to seat it all the way down to where the flange is on top of and retaining the pins in the worn driven gear.

[pic]

Once this is done you can re-install the mechanism cover and, in the case of the convertible rear motor, the mounting flange. Once it is together, I highly recommend you use a battery and some test leads into the connector to run the motor in both directions to be sure the electrical motor works as it should. If all goes well, put the window motor back in and enjoy a nice drive.

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download