Deck Sealant Replacement

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
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Deck Sealant Replacement

Postby Todd » Mon May 21, 2018 10:58 am

Hello all. Now that spring has finally arrived in Michigan I am working my way down the project list for my 2003 160 Dauntless. This boat spent [its] first 14 years in Florida. The flexible (silicone) sealant found in the deck joints and other areas has unsightly mold spots that won't respond to any cleaner.

I would like to pull out the old sealant and replace it with something suitable. Having never done this type of project, I'm seeking the wisdom of those who have. I presume I will pull out the old sealant and reapply new, but would like advice:

--what sealant to use as?

--what tools are useful?

--how best to accomplish this task?

Thanks very much.--Todd

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Phil T
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Re: Deck Sealant Replacement

Postby Phil T » Mon May 21, 2018 12:31 pm

Todd--Lessons learned:

  • Take your time, don't rush.
  • For removal - plastic putty scrapper, nothing sharp that can damage brittle gelcoat.
  • Tape off the sides of the seam with painters tape.
  • Apply a sealant and not an adhesive/sealant product. Suggestions include Boat Life or Sikaflex branded sealant.
  • Cut the tip at a 15% angle so that it is as wide as the seam.
  • When you apply remember you want to angle the tube so that you get the caulk into the gap and leave a smooth edge.
  • Slow and even pressure as you go. Try not to stop.
  • The more you mess with trying to fix imperfections, the worse it will be.
  • Let cure a day, then pull the tape.
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Re: Deck Sealant Replacement

Postby Acseatsri » Thu Jun 14, 2018 4:42 pm

Another piece of advice:
Push the caulking gun forward when filling the seam.
I always tool the seam with a plastic edging tool for caulk.
Pull the tape as soon as possible after tooling. If the caulk starts to skin over before removing the tape, it will be hard to make it look decent without re-shooting it.

BTW, a big heads up to using Boatlife Lifeseal.