Re-sealing deck hatch. Best sealant?

[davethedog]

Afternoon all,

Looks like we have a small leak in the forward deck hatch and so looking to remove it and then re-seal it if I can. What sealant do people recommend for this task please?

Thanks in advance

DTD

 

[AngusMcDoon]

Butyl rubber tape. You can cut it with scissors. No mess. It never sets completely so remains flexible. Can be cleaned up at any age with white spirit. Keeps forever. And most importantly, when the inevitable happens and you have to redo it, you can get it off easily. Sikaflex and similar is an expensive wasteful messy curse compared to this stuff, especially when it comes to removing old sealant that has failed or hatches stuck in place with it.

HIGH PERFORMANCE BUTYL SEALANT MASTIC TAPE - 8MM X 6 METERS LENGTH - GREY | eBay

Various colours and thicknesses/widths available. If you get it too thick it squeezes out when you clamp down the bolts and the excess can be cut off with a Stanley knife.

 

[RunAgroundHard]

+ 1 for AngusMcDoon idea.

I used similar stuff to rebel my galley hatch. It was leaking and on removal all the old sealant just crumbled away. So far rebidding on butyl mastic strip (just like the link) has proven to be a good repair. Job done this summer, experienced biblical rain frequently in Argyll and Bute area, not a drop. I have other fittings on my boat sealed with butyl mastic for years now, and no leaking.

My fore hatch, which was professionally installed about 4 to 5 years ago, was bedded on a more usual "mastic" and it too has remained water tight. As a DIYer the butyl tape is just easier on the wallet and skill level.

 

[Rhylsailer99]

When i first got my boat I had no idea and used silicon. Its been fine ever since but knowing what I know now I would use Butyl tape for sure.

 

[davethedog]

Thanks all and will see if we can get some butyl out here in the Caribbean!

 

[Boathook]

Or butyl mastic 'putty' in a tube.

 

[AngusMcDoon]

Thanks all and will see if we can get some butyl out here in the Caribbean!

Window installers use it.

 

[Keith 66]

I am in the process of resealing my Sabres windows, the makers assembled them with Butyl sealant. At 8 years old they started to leak, At ten years old the butyl had hardened & cracked into sections about 1" long. This year i had to pull them out. Butyl is good when it isnt exposed to UV but as a window glass to frame sealent its crap.

 

[Boathook]

When I rebuilt my windows I used a black butyl sealant to seal the glass in the frames as recommended by houdini windows. Over 20 years on still sealed and doing the job.
The grey butyl is affected by uv where exposed.