collected wisdom
This is a composite of several responses to the same question on Sailnet's Catalina mailing list. Hope it helps. 1. Remove the fastening screws. Heat the alum with a hair dryer or heat gun. Softens up the sealant. Insert a putty knife about 1-1/2" wide (careful with the gelcoat) and pop out one corner. Then you are going to take the putty knife and just go along breaking the seam all the way around until the entire edge of the window comes out. 2. Make sure that the indented surface is absolutely clean. Lacquer thinner works well. In all likelihood, silicone has been used for the frame-to-hull seal on your windows in the past. Well, NOTHING sticks to silicone. If you don't get all of the silicone cleaned off of the window frame, it's going to leak. Use single-edged razor blades or a screwdriver (straight)or a knife, and finally sandpaper to the frame cleaned up. Keep running your fingers over the surface until you can feel no more silicone. 3. Check the frame for straightness... a bent frame will more likely leak again. Put the window in the opening to see how it fits against the cabin top. Are there gaps? As a guide, mark lightly with a pencil around the frame, or at the corners so you know where the frame fits in correctly. You want to get it right the first time -- not reposition it. 4. Replace the seal. Lay a butyl rubber seal onto the back side of the frame. You can get a big roll at your friendly RV dealer for a couple bucks. It's used for setting RV windows and the like, just like on your floating RV. It comes in both black and off-white -- with the white being a little more "sticky," flexible, and easier to use. A. Put the butt joint of the seal at the BOTTOM of the window. B. Don't overlap the ends by making the seal too long. Just butt them so there's pressure holding the two ends them together. C. LAY the rubber in -- don't stretch it in place. You want as much body to it as possible. Pulling and stretching it onto the frame will end up with less "meat" to seal the joint. 5. Replace the window. Go for it. Put 'er back in place and evenly take up on the screw to seat the rubber. Don't distort the frame. Just an even pressure all around. 6. Finish off A. Let the butyl rubber set overnight and wait to pull off the excess that oozes out around the frame outside. It's best done when it's cool weather outside. B. Immediately carefully trim the excess off with a razor knife or X-Acto knife.
