Installing Early One-Piece Windows

I am writing this presuming that you will be installing your one-piece window kit over a weekend, taking your time, and allowing things to dry before moving on.

(Friday night)

First, remove the door handles and window cranks by tapping out the pins that secure them to the shafts (you will have to push the door panel into the door a bit to get at them). Remove the door panel afterwards by gently prying it away from the door using the flat screwdriver. Next, remove the stock window regulator and glass from the door. Remove the U-shaped run channels, as well as the lip seals that run along the bottom of the opening.

Next, remove the vent window. It should be held in by two screws and a 10mm bolt. Remove these and the vent assembly & post will pull straight up and out. Remove the rubber surrounding the opening at this time as well.

If you look down into the door, you will notice a metal channel directly below where the vent window used to be. You can use either a hammer & chisel or a drill to either break away or drill out the spot welds that secure the channel inside the door. Break loose the weld on the metal tabs under the channel afterwards and bend the tabs down and out of the way. Once you're done, line the entire length of the newly exposed sheet metal at the bottom of the window opening (not just the vent window area) with a couple of layers of masking tape to prevent scratching the glass as you test fit everything.

Next, locate the holes for the window regulators. Hold the regulator up against the sheet metal of the door and locate the window crank shaft over the center of the original location. Transfer the location of one of the mounting holes as best you can. Use a small drill bit to drill the hole and use a small round file to enlarge it later. Then install the regulator inside the door with the back of the regulator still outside the door (you will see why in a moment). Install one of the two mounting bolts in the hole you just made to secure the front of the regulator. Then using a small level, take a reading on the level of the bottom of the door. Take note of where the bubble lies and move the level up to the horizontal brace of the regulator. Then lift up on the back of the regulator until you get an identical reading (you will want the bottom of the regulator to be parallel with the bottom of the door). Mark the rear mounting hole and remove the regulator from the door. Create the rear mounting hole as you did the first and then install the regulator properly inside the door. Secure the regulator at the rear location.

Next, take the U-shaped run channels and bend them so that they follow the shape of the window opening. The run channels are longer than necessary and the excess material should be used at the back of the glass, not at the front. The fabric material may want to separate from the rubber of the run channel at the point where you bend it. If it does, simply make a relief cut in the fabric and use some weatherstrip adhesive (3M part #08011) to rebond it. Install the run channel into the window opening (you can use masking tape to hold in place until the next step).

Lower the glass down into the door and rotate it until it is upright, then lower it into the sashes of the window regulator and roll up the window tight. The glass should fill the window opening perfectly. If not, slot the two holes you have just created until the glass fits level inside the opening. Once you have everything level, mark the positions of the bolt heads on the sheet metal. Remove the glass and the regulator, position the regulator against the door, and drill out the third hole. Reinstall the regulator using all three mounting holes (make sure the bolts you use aren't too long that they interfere with the glass) and reinstall the door glass. Allow the run channel to drop down and apply some contact cement to it and the metalwork inside the window opening where the run channel will bond. Let it dry until tacky and reposition the run channel, rolling up the window to hold it in place while it dries.

(Saturday)

Mark the postion where the glass fits into the U-shaped sash attached to the window regulator (mark both the sash and the glass). Remove the glass from the car and remove the sash from the regulator (make a note as to which way it faces inside the door). Use the piece of cork or rubber material included with your new sashes (you will have to come up with your own material if you are using used sashes) and wrap it over the edge of the bottom edge of the glass where it will fit inside the sash. Line up the sash with the bottom of the glass (making sure it is right-side up) and gently tap it on to the glass with a rubber mallet. Once the sash is tight and fully seated, reinstall the glass and let it rest at the bottom of the door. Optionally, you can use something like Automotive Goop™ to bond the glass to the sash inside the door if the lip seals are all ready installed (you may need to do this if you were replacing a broken window). I talk more about the Goop™ method at the end of my Power Windows article. You can remove the masking tape along the bottom of the window opening at this point.

The next step is to secure the four felt lip seals along the inner and outed edges of both doors. Now I prefer the old-style felt seals over the newer snap-in seals for a number of reasons. Firstly, the clips don't really secure the strips securely enough. Second, the rubber-to-glass fit was extremely tight, creating a lot of friction that had the seals flipping over every time you tried to lower the glass (the seals would actually cock slightly when you tried to roll the glass up, bringing the bottom of the seal in contact with the glass which increased the friction even more). Third, the soft pliable nature of the snap-in seals is a bit too supple, creating a wavy-like fit if the seal and glass weren't perfectly— and I mean perfectly— parallel. Finally, they were actually more work to install than the old seals. Ooh— and they're more expensive to boot!

Normally the felt lip seals will fit pretty tightly when the glass is installed. Optionally, you can trim off about 1mm from the lip of each seal to increase the available space between the lip seals so that the glass doesn't fit quite as tight. Don't worry... the lip seals don't have to press against the glass hard to wipe the water off when you roll the glass down and up. I even trimmed a bit more of the lip away on the outboard sealing strips, beginning at a point where the original vent window post was, forward (the sheet metal makes a noticable shift inboard at this point and I bent the lip seal slightly to follow its contour; see image at right). Accurate trimming was accomplished using a small, hand-held device that used to be available in many hobby shops. It is normally used to cut thin, parallel strips of balsa from a larger sheet. I only trimmed mine because I already owned such a device (you may want to see if you can even find one first).

When one-piece window kits first came out, many people simply installed the felt lip seals as straight components. The ends of the seals would dissappear into the voids of the lower corners of the window opening, looking far from factory. Some people, however, trim the ends of the felt strips so that they can curve up at the ends to match the curvature of the lower corners ofthe window opening. This is what I did for my '56 and what I just finished doing for my '63.

Beginning about four inches from each end, make a cut in the metal-reinforced area every ¼" all the way to the ends. Make the cuts using a pair of metal tin snips or shears, cutting right up to the small lip that lines up with the top of the door. All that relief cutting will cause the seal to warp slightly but you can flatten it out very easily. Next, gently bend the ends upwards in graceful arcs to match the window opening as close as possible. Once you have the lip seal bent correctly trim off the excess as I have shown in the following photograph. This is necessary to clear the U-shaped run channel at each end.

Next, get a good brand of weatherstrip adhesive (3M part #08011) and smear a thin, even layer over the entire contact area of both outboard lip seals, as well as the sheet metal to where they will be bonded. All surfaces should be as clean as you can get them. Be sure to distribute the adhesive in the window opening over the entire contact area as well. Let it dry for at least fifteen minutes before bonding the seals in place (you should apply the adhesive in the shade so that it does not dry out). Secure it in place with clothespins from up inside the door and let it sit for a few hours (the more time the better and overnight drying is preferable if you have the time).

Now is a good time to fabricate the lower mount. You will need a piece of stiff metal about 1" wide by 6" long for each door. Place the mount at the bottom of the door and drill a hole to mount it. Line up the top of the mount so that the tab at the bottom of the window regulator is between you and your new mount. Drip a hole and bolt the regulator to the mount.

Once the outer lip seals have had sufficient time to dry, use the same procedure to secure the inboard seals (remembering to wait at least fifteen minutes before bonding). Clamp it in place with clothespins and let them all dry overnight. You want the adhesive absolutely dry before you install the glass (you don't want the lip seals peeling away from the metalwork when they flex against the glass as it rolls up and down). You can see how the lip seal conforms to the contoured sheet metal at the point where the factory vent window post was while remaining straight where it comes in contact with the glass.

(Sunday)

Once the lip seals have had plenty of time to dry, remove the clothespins and reconnect the sash (and glass) to the window regulator. Roll the window up and down and make sure that everything works right. If the window glass doesn't want to roll up inside the run channel, you can grab the regulator at the bottom near the rear edge of the door and pull backwards (an inch is all it takes!). Contrary to what I've read in the instructions that come with the kit, you want to do this with the regulator firmly mounted inside the door. To unbolt everything except one forward bolt like the instructions suggest could very well mean that the sash will end up too far forward on the glass (the instructions mention that the rear mounting hole may need to be redrilled, resulting in the glass being located further rearward). You may still need to adjust your fabricated lower mount afterwards, however.