How To Install A Convertible Top
Article by Ron Fryer
Note: these are instructions for pre-made tops.
- The first thing to check before removing your old top is the frame. Run it up and down several times, checking for binding or areas that pinch the fabric. Make sure both sides go up and down evenly. Make notes of any irregularities. Take the new top and drape it over your old top to compare the fit.
- Raise the top halfway and remove the bow header strip. This is the bead that runs across the front of the top. It is stapled in, and should pull off easily. There may be a metal strap screwed over the edge of the material. Remove the screws and the strap and set aside. Remove all the staples across the header bow. This should free the front of the top.
- Remove the forwardmost side rail weatherstrips on both sides, along with the quarter side rail weatherstrips. These both bolt on from the backside of the roof rail. There may be a Phillips screw in the ends on the weatherstrip side. You will have to look for these, as they are often embedded in the weatherstrip. Pull the fabric strips off of the quarters. They are glued to the metal.
- Look for the ends of the side cables and determine which end will be removed the easiest, and remove the end of the cables at one end, leaving the other end attached. Pull the cables out through the pockets in the edge of the top, and drape inside the car.
- Check the second and third bows to see if there are any screws attaching the top. If there are, remove the screws and slide the metal bars out of the listings (pockets) and set aside.
- Put the top in the up position and latch the front. Remove the wire-on from the top of the rear bow. It is stapled on. Remove the rest of the staples across the rear bow. Some of these may be difficult to see, so some probing may be necessary to locate them all.
- Go inside the car and remove the well or loosen the side of the well so you have access to underneath. You should be able to see a metal strip about one and a half inches high with a series of bolts through it. This is the rear tack rail. Using the correct size socket, remove the bolts. There should be 11 to 15 of them, and they should go the entire length of the tack rail, all the way around to the side of the car where the top pistons are. When all of the bolts are removed, the back of the top should be loose. Some GM cars use a "floating bar" that just has a couple of bolts in the ends. For these you will need a flat ratchet, as they are facing the outside of the car.
- After the rear tack rail is loose, go to the outside of the car and place a heavy blanket or fender covers over the rear of the car around the convertible top opening. Drape the blanket into the opening and lift the rear tack rail out of the hole and place it on the blanket. Remove just the staples that go through the convertible top on both sides. This should be the last thing holding the convertible top onto the car. Remove the top and set aside for later use checking and marking the pattern.
- If you are not installing a new window or pads, skip down to # 12. If you are not installing pads skip to #11.
- Remove just one side pad. These staple on the ends and sometimes to the ends of the middle bows. On some cars there are screws holding them onto the center bows. Some cars require that you open the pads up to remove the pads. After one pad is off, lay a yardstick vertically down the center of the rear window to the edge of the finish molding surrounding the top opening. The yardstick should be leaning across the rear bow, and you should be able to read the measurement at the back edge of the rear bow. This should correspond to the measurement designed for your car. If you do not have this number, we will be happy to provide that measurement. Attach the pad in the same manner as it was attached originally, making sure that they are snug.
- To remove the rear curtain, take out the staples along the rear tack strip and from across the rear bow and the rear window should lift right out. If your pads are on top of the rear curtain and you are not replacing the pads, just cut the rear curtain around the pads, and install the new rear curtain over them. When installing the new rear curtain, first find the center of the rear bow and mark it. There is usually a small notch in the top of it. Staple the center of the rear curtain top strip to the center of the rear bow, aligning the edge of the rear curtain top strip to the front edge of the rear bow. Staple the remainder of the rear curtain top strip to the rear bow, pulling to the outside of the car slightly to smooth out the wrinkles as you go along. Next, align the center hole in the lower part of the rear curtain with the corresponding hole in the rear tack strip. Staple the center of the rear curtain to the center of the rear tack strip. Then work your way out to the edge of the rear curtain in the same manner as before. Unlatch the front of the top frame and brace up about a foot with a 2X4. Bolt in the rear tack strip with just three to five bolts; one in the center and one at each end of the clear part of the rear curtain, and maybe another on each side. Close and latch the top. If there are any wrinkles, you can either pull them out along the top if the rear curtain assembly or along the rear tack strip. You can mark the locations with chalk or another removable medium. Make the adjustments on the rear bow first, then to the rear tack strip. If necessary. When you are finished installing the rear curtain, measure the bow height again to ensure a proper fit.
- Before installing the convertible top, lay it out on a table or clean floor, with the old top over it. Line up the edges along both sides and then mark on the new top where the bolt holes went through the old top. Some people prefer to mark where the top edge of the rear tack strip hit the old top on the new top. Either way will work. This is an important guide to where the top is supposed to fit on the rear tack strip, and will save you a lot of time.
- Now that the back of your new top is marked, lay the new top over the frame in a position that is fairly correct. If you removed any metal strips from the listings in the old top, slide them into the appropriate listings now. Then, using a long wire or straightened coat hanger with a "u" shape bent into one end, slide the wire through the side pocket of the convertible top and hook the end of the wire to the side cable and pull it through the pocket. Do the same on the other side. Raise the top frame about halfway and connect the side cables to their appropriate places. Move the top frame to the up position and latch the front. The cables should be tight, and align the top from side to side. Now, you need to slide the top either forward or backward to place the quarter flaps in the correct place. The seam that holds the quarter flaps to the top should line up with the edge of the convertible top frame.
- Begin stapling the rear quarters of the top to the rear tack strip, beginning at the end of the tack strip, or toward the front of the car. With a few staples in place, pull the quarter of the top around the bend in the tack strip, stretching it slightly, and staple the other end. Then pull down on the top at the curve until your alignment marks are in the right place, and staple the top to the tack strip. Finish stapling until there are sufficient staples to hold the top in place. Do the same for both sides. Then bolt in the rear tack strip with just a few bolts, like before.
- At the front of the car, with the frame still locked, pull the side of the top forward until most of the wrinkles disappear. While holding the top forward, Mark the top at the front edge of the frame on both sides. Now raise the top halfway again. Pull the front of the top around the front bow so as to fold it around the bow. Pull the top ½" past the front edge of the bow, fold under and staple between the outer edge and the seam on both sides. Shut the top and latch it. The sides and quarters should now be smooth and the rear bow should line up at the darts in the top. If you have wrinkles, mark them with chalk and go back and make the adjustments using the instructions in step 14. When your top in wrinkle free, mark the rest of the front of the top and staple the front. Add the front roll that you removed earlier by stapling under the flap.
- Apply contact cement to the quarter flaps and the front side flaps, and let dry. With the top latched, pull the flaps into position and glue down. Raise the top halfway and install the weatherstrips.
- Staple the wire-on across the rear bow with the flap of the wire-on toward the front of the car, taking care to apply it straight. Bend over the top and hammer flat. Install the end caps.
- Now go inside the car and install the rest of the bolts. Replace the well, and you’re done.
- Leave the top up for at least two days to allow it to set.
Upholster Magazine Online by Ken Bowles, Rostov Upholstery Supplies