The original rear window seals had largely perished, hardening, cracking, and shrinking to leave significant gaps at the bottom of the windows, the largest opening being about an inch long. The two part system in comprised of a sealing strip and a centre filler strip. Judging by the current condition and surface textures the factory seals were made from a different material than the filler strips. The glass all appears to be the original factory installation as well.
Initially the plan had been to leave the old ones in and replace them at the same time as working on the roof/top paint, however as the other roof leaks were taken care of it became evident the windows were leaking a little more in a couple of places than what could be tolerated during the island’s wet season. So when the winter weather cooperated with a couple of dry days the decision was made to go ahead and replace them now even though it means they will need to be reinstalled again later.
The Removal:
The first step of removal is to pry or pull out the filler strip starting from the top centre and working around to the bottom corners. The original seals are quite stiff and difficult to flex so the best way to remove the glass is to then cut carefully along the edge of the glass through the rubber lip starting from the top and down each side. Leaving the bottom in will help prevent the glass slipping out unexpectedly. With an extra pair of hands, press the glass outward at the top and it will hinge on the lower lip and lift out. With the glass out the remainder of the old seal should slide off of the aluminum easily. The window glass and edge of the opening can be cleaned and wiped in preparation for the new seals. This would also be a good time to paint, if the circumstances allowed!
The Installation:
The new seals are cut square and flat on one end, fit into place over the aluminum around the opening, and measured and marked to 1 inch overlap then removed and cut square and flat on the other end. They are reinstalled starting from the bottom centre and compressed slightly to absorb the extra inch of length. This will help the seal the joint and combat the effects of shrinkage over the years.
Once the new seal is in place the glass is reinstalled, beginning with the bottom edge and working around the sides and top. This is one of the more daunting steps and cannot be rushed as it must be carefully worked into place without dropping or chipping the glass or tearing or puncturing through the seal with a tool. An extra pair of hands is helpful and can be necessary if the seal needs to be pushed outward from the interior along the sides or top. Likely the addition of some dish soap would make some aspects easier but it is possible dry.
The final step is to install the filler strip down the centre of the seal on the exterior. This expands the seal and traps the glass and aluminum firmly in place. A specially designed tool was originally used and can be seen in the manual but a custom homemade version was all there was to be found in this case. Perhaps this could be done with the help of dish soap and some other type of tool, but it seems it would be very difficult to work it in without this type of tool to expand the gap without tearing the rubber. The filler strip is inserted starting from the top centre and cut with 1/4 inch overlap that is worked in on top to prevent a gap from shrinkage. To finish, the strip width is checked all the way around and any areas needing to be tucked in further are pressed with a wooden block or using the tool handle as a roller.
