I've replaced one and am replacing the second
Lewmar SuperHatch which is very similar. After 34 years they were not leaking, just impossible to see through. This shows a gold color where I used Alumiprep and Alodine to touch up the original anodize that had been scratched during
removal of the old butyl and
sealant. If left untreated, this is where
corrosion could start. You'd never see this if I'd used clear rather than gold alodine.
The original manufacturers used Window-Weld butyl 34 years ago to
bed the
acrylic and then
sealant around the edges. Window-Weld is available from any NAPA or most other car
parts stores and as mentioned, it lasted 34 years. I've used it on a lot of airplane windshields and the two tricks are cleanliness and to lightly warm the frame and
acrylic to ensure there is adhesion before filling the gap with sealant. As long as the surfaces are clean (and that is the key) I have never had a problem with 795