Sorry I'm late to the party!
Hope you check back again. As usual, Lance's info is spot on, but I'll share my experience replacing the rub rail and backer.
In my case, the rub rail itself wasn't bad, but the white backing was cracked in lots of places and looked like crap. Some helpful points-
- the backer plate is held on by 7 billion stainless steel screws. I know I was the second person to replace the backing, because there were actually 14 billion holes underneath! MANY of my screws were bent, surprising given their thickness. After removing the backing, I filled all the holes with 5200. As we all know, it will outlast the boat, and since I was using it as a filler and not an adhesive, I felt comfortable using it.
The backer plastic has predrilled holes, but if the hole lines up with an existing filled hole, just drill through the plastic near it. It drills easily, doesn't crack. I never used pilot holes, but maybe I just got lucky.
Using a heat gun for the bow and aft corners- works great, but care is called for. I screwed the plastic tight right up to the turn, then tried to bend the plastic around the corner, while applying heat. Patience is called for- the heat gun appears to have no effect at first, but suddenly the plasticgets REALLY soft. make the turn around the curve, and put in another screw and you're done. Rushing actually leads to the plastic liquifying JUST before it turns brown.... or so I've heard...
I wasn't satisfied with the first side, and actually redid it. While it seemed like the rail was perfect, as I stepped away from the boat and looked down the side, I could see that the screws weren't on a perfect line. It becomes more obvious when you install the black rubber...a slight wavy look. "Wavy" sounds alot better for a boat than it looks.
I caulked the seam with lifecaulk, because I also had leaks when heeling hard, or in rough seas. It works well. I also, as Brian said, caulked the screws- actually drilled the screws 3/4 down, then caulked under the head. Was a little sloppy, but when the rubber goes on, it's all hidden anyway.
All in all, an easy job, and really made a difference visually. Good luck..
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