Re new deck caulk seams

[Albesaurus]

Happy spring! I decided to dig out and replace the caulk joint of the fuel tank access on my 02 engine box 28TE. The caulk i am removing is silicon like and i am not sure what it is. I want to replace it with the proper caulk/marine silicone.

Any suggestions on this project? Life caulk? Other. Obviously its an access so minimum water proof seal is what i would say.

See photos

Nick

[gmberkley]

I placed painters tape on both sides of the joint, and used Boatlife Life Caulk to fill the joints, then removed the tape.

[Albesaurus]

Thanks Gregg. I did wind up using boat life life caulk. I will say though that while i was at west marine getting ripped off ( $34 per tube). There was a marina tech in the aisle with me. He told me the best caulk is a UV resistant 4000 adhesive. I said that its not necessary to bond as much as it is to seal out water. He said true but the UV will break down the life caulk in less than 5 years and it will turn yellow and shrink/fail.

Because i will need to get into this access in less than that time. I went with the life caulk to make the removal easier.

Very tedious job! It took a full day to remove all the old caulk and an hour to re caulk. I used two full tubes. I did not use painters tape. I used my thumb wet with water and a little soap to smooth out the joint. Its a better job than the original but not perfect. Its also bright white against the vanilla colored deck.

[Banjamm1n]

Ours had a thin braided rope under the caulking at the front, it made removal of that section much easier once I found it
I might try doing it all around on re-installation

[GSSeattle]

Ours had a thin braided rope under the caulking at the front, it made removal of that section much easier once I found it
I might try doing it all around on re-installation

They probably used that as a bond breaker. The idea is to only have the caulk / sealant bond to the sides of the joint, allowing for more flexing and less chance of failure. Evidently when sealing a u-shaped channel, if it bonds to three sides then it won't flex and it will lead to early failure. When I re-did the seam around the pilothouse, I used bond breaker tape along the bottom. Quick google search on bond breaker should give you more info.

[Banjamm1n]

Ours had a thin braided rope under the caulking at the front, it made removal of that section much easier once I found it
I might try doing it all around on re-installation

They probably used that as a bond breaker. The idea is to only have the caulk / sealant bond to the sides of the joint, allowing for more flexing and less chance of failure. Evidently when sealing a u-shaped channel, if it bonds to three sides then it won't flex and it will lead to early failure. When I re-did the seam around the pilothouse, I used bond breaker tape along the bottom. Quick google search on bond breaker should give you more info.

Had no idea, thank you!
I’ll do some research on it

[Albesaurus]

Update. The boat life caulk lasted only one year before yellowing and cracking… next time I spend a full day pulling out caulk i will replace it with UV resistant 4000. Like i was told to use but didn’t listen!?$!?

[Mike Monte]

btw: I just ordered eight 3M UV4000 white cartridges from Amazon @ $15.22 per unit.

I used Life Caulk to redo a seem last season - it "yellowed" by Sept....never again...

I plan to re-bed my portholes before May and will use the 3M4000.

[Nancy]

Hate to say this, but we used 3M 4000UV at the pilothouse joint a few years ago and it yellowed within a year. I wasn't happy. Yes, it could be sort of cleaned with a toothbrush and Soft Scrub with Bleach, but that shouldn't be necessary.

[GSSeattle]

I've had good luck with Life Seal (not Life Caulk). Made by BoatLife as well. Hasn't really yellowed, but does catch some dirt. Dirt does wash off easy. Unlike the 3M products, a half used tube of Life Seal will still work in 6 months. Handy to keep around for small projects.

I've also used Sudbury Sealant in the past, but it is much thicker and harder to work with.

[Harp31]

Last 3 boats I’ve recaulked all seams with black uv 4000. Some people hate the look, but it stays crisp and clean for years.

[LillianpFD]

Last 3 boats I’ve recaulked all seams with black uv 4000. Some people hate the look, but it stays crisp and clean for years.

You have any pictures of the black? Thx.

[Mike Monte]

I used Life Caulk last spring to re-seal around cabin of my 28TE. It yellowed/cracked/LEAKED by September.
I re-caulked around the cabin again this season using Pettit AnchorTech Advanced Hybrid Sealant.
*fingers crossed*

[Mike Monte]

I used Life Caulk last spring to re-seal around cabin of my 28TE. It yellowed/cracked/LEAKED by September.
I re-caulked around the cabin again this season using Pettit AnchorTech Advanced Hybrid Sealant.
*fingers crossed*

The Pettit sealant (mentioned above) worked well through the end of the season.
Hopefully I'll get a few seasons out of it.

fwiw: This past spring a tech (from Standish) replaced my fuel tank. He also used the same sealant. He said that it was the best for sealing deck seams.

[Nancy]

The Pettit sealant (mentioned above) worked well through the end of the season.
Hopefully I'll get a few seasons out of it.

fwiw: This past spring a tech (from Standish) replaced my fuel tank. He also used the same sealant. He said that it was the best for sealing deck seams.

Good to have this input, Mike.