Sealing Deck Fittings

dlochner · Mar 25, 2022

The only effective long term cure is to remove and rebed.

There is a good article on this at MarineHowTo.com.

FastOlson · Mar 25, 2022

After your boat reaches about 20 to 25 (max) years, ALL of the deck fittings must be removed. Over-drill, epoxy fill, and re-drill all of the holes. reattach with good sealant. And.... you may well have to re-core some areas where the prior owner(s) allowed moisture to rot the coring.
No boat is immune, altho the higher quality brands can go as long as 30 years before hardware re-bedding is required.
West Sytems and a host of other good sources have web and print info on this process.
The work is tedious, but within the skill set of any determined owner. It's just time (yours) or money (yours).

I just did this to our boat last year because it was (1) due, and (2) because of Covid we were not going anywhere with it and needed to stay isolated for quite a while. The whole boat was professionally painted, and our part of the deck redrill and epoxy work took about 3 months.

Good luck! From the description, you have work to do. Perhaps one lucky thing is that if.... the water is leaking thru to the inside easily, maybe it is not soaking significantly into the coring on the way thru.

Post up some pix when you can. I have a blog with some pix of our deck work, if you want a link.

mikeracca · Mar 25, 2022

Plymouth Sailor said:
Thanks, though I know you're correct and that's the right way to do things, working a 60 hour a week job doesn't afford me that type of time. Any suggestions on a temporary solution?

If there is no rot or other damage you won’t need to go as far as stated above. Simply remove the stanctions clean the stainless and the deck then rebed with some 3M 4600. When I do the job, I have been very successful with putting a thin bead around each bolt hole, and around the base of the sanction itself and also some on the top most part of the bolt as well. Wipe any excess off before it hardens for best results.

jviss · Mar 25, 2022

mikeracca said:
3M 4600

? I don't think there is such a caulking product.

That said, anything that hardens or is a permanent adhesive is not a good idea. Something that adheres but stays flexible is best. 3M used to make 101, but no more. The best thing, in my opinion, is butyl tape. @Maine Sail used to sell the best stuff, but since his stroke has ceased operations. I think if you are willing to drive to his place in Maine he'll see you some.

jssailem · Mar 25, 2022

mikeracca said:
3M 4600

4650-6000 3M | 3M, 4600, 50 Way, 2 Row, Right Angle IDC Connector | 121-0371 | RS Components
My suspicion, this was a typo...

Temporary fixes are just that, temproary. It is like plugging the Dutch tidal dike with a little boys finger... Works for a while then it gives way. I sense you are thinking, if I can just stop the water coming in for a while I can go sailing. While I applaud the intent I caution with the usual results. The temporary nature of the "fix" gets put on the back burner. The power of water too find ways of entering your boat are legendary. @FastOlson has outlined the positive fix. If you prefer the quickie fix be sure you do not choose a method that will permanently affect your boat and likely not fix the problem.

Avoid 3M 5200 (Often called "The Devil's glue") or anything Silicon promising to seal your holes forever.

Caulks from vendors like BoatLife, 3M - 4000UV, and Sikaflex 291 (1-component polyurethane sealant specifically developed for the marine market, which cures on exposure to atmospheric moisture) provide a flexible marine polysulfide or Silyl-Modified Polymer caulk identified as "removable - not permanent". They can give you 12-18 months of less water intrusion.

You will be able to remove the fittings, clean up the attachment area and then reinstall the hardware in a more assured manner.

jssailem · Mar 25, 2022

I agree with the use of Bed-It Butyl Tape as a bedding material between fixtures that manually hold an item in place. Good sealing/caulking, flexible, removable. Great features for fittings on a boat.

Hello Below · Mar 25, 2022

jssailem said:
View attachment 203789
4650-6000 3M | 3M, 4600, 50 Way, 2 Row, Right Angle IDC Connector | 121-0371 | RS Components

Boy that brings back some (almost) lost memories.

Scott B · Mar 25, 2022

jssailem said:
I agree with the use of Bed-It Butyl Tape as a bedding material between fixtures that manually hold an item in place. Good sealing/caulking, flexible, removable. Great features for fittings on a boat.

Unfortunately, Bed-it is no longer available and stores have all been cleaned out of existing stock.

Edit to add previous comment by Maine Sail I am in talks to sell the formulation/brand, but no firm deals yet...

kloudie1 · Mar 25, 2022

May not be as good as Bed-It but probably useful!
Trimmable Butyl Tape 1" (30 Feet) (sailrite.com)

LloydB · Mar 25, 2022

I had a similar problem with my trailer sailor and tried the temporary fix by covering it up and the boat still leaked like a sieve a reduced leakage but still a sieve. Looked and looked and thought and thought and could not figure out how so much water could get into my boat on a trailer with the cockpit covered with the tarp.(about three weeks past Labor Day) A better tarp seemed to work until late spring but found it wasn't the solution and added confusion. So I bit the bullet and got mainsails butyl tape and bedded everything that I could. The result was no tarp no leaks managed to stretch the work into two weekends between games. It's a sailboat even in a calm I'm already there.

Tally Ho · Mar 25, 2022

I have fixed many deck leaks…from cleats & stanchions mostly, but also handrails. Each required removing the thru bolts, taking the nuts off from inside, along with whatever backing plate was used. On my cleats and stanchions had aluminum backing plates, the handrails just had washers.

Then I removed the attachment, cleaned the deck under it, chamfered the hole a bit on top, put the bolt back through the attachment and put some butyl tape around the bolt tight under the thing being attached. I form the butyl into a little cone. Then put the bolts in the holes and press down. The put the backing plates and nuts back on from underneath. The butyl will squeeze out over time. Trim it and tighten the nuts again after a few days.

Bed-it butyl is THE best I have found, but sure you can get it now. I bought some other stuff on Amazon, and it was ok, but nearly as good.

I do most of this work myself. Holding the bolt (or worse a screw) while getting the nuts tight is not easy. I prefer hex-head bolts to round-head machine screws. I have 5 vice-grips that I clamp o the bolt heads, then I can get the nuts on and tightened.

If there is any coring in the deck, it is best to over drill the hole, fill with thickened epoxy (WestMarine Six10 in the cartridge works great for this), then drill the correct hole for the bolt. I upgraded winches over the winter, so drilled and filled many holes. Then redrilled, chamfered, and used Bed-it with bolts to mount the winches.

Rained for days after I took the winter cover off last week…and no leaks.

Greg

mikeracca · Mar 25, 2022

jssailem said:
View attachment 203789
4650-6000 3M | 3M, 4600, 50 Way, 2 Row, Right Angle IDC Connector | 121-0371 | RS Components
My suspicion, this was a typo...

Temporary fixes are just that, temproary. It is like plugging the Dutch tidal dike with a little boys finger... Works for a while then it gives way. I sense you are thinking, if I can just stop the water coming in for a while I can go sailing. While I applaud the intent I caution with the usual results. The temporary nature of the "fix" gets put on the back burner. The power of water too find ways of entering your boat are legendary. @FastOlson has outlined the positive fix. If you prefer the quickie fix be sure you do not choose a method that will permanently affect your boat and likely not fix the problem.

Avoid 3M 5200 (Often called "The Devil's glue") or anything Silicon promising to seal your holes forever.

Caulks from vendors like BoatLife, 3M - 4000UV, and Sikaflex 291 (1-component polyurethane sealant specifically developed for the marine market, which cures on exposure to atmospheric moisture) provide a flexible marine polysulfide or Silyl-Modified Polymer caulk identified as "removable - not permanent". They can give you 12-18 months of less water intrusion.

You will be able to remove the fittings, clean up the attachment area and then reinstall the hardware in a more assured manner.

Yes typo… 3M 4200 is what I was meaning to say. It’s not nearly as permanent as the 5200 and it hold good, but can still be removed. It’s not like silicone in it smell or feel. I have used it to seal the holes in Lilly and it works a charm.

mikeracca · Mar 25, 2022

jviss said:
? I don't think there is such a caulking product.

That said, anything that hardens or is a permanent adhesive is not a good idea. Something that adheres but stays flexible is best. 3M used to make 101, but no more. The best thing, in my opinion, is butyl tape. @Maine Sail used to sell the best stuff, but since his stroke has ceased operations. I think if you are willing to drive to his place in Maine he'll see you some.

It was a typo I was meaning to say 3M 4200

https://www.3m.com/3M/en_US/p/d/b40066971/

Thats the calking gun version, but it’s also available in squeeze tubes.

jssailem · Mar 25, 2022

Be advised that 3M 4000UV has experienced failure.

3M UV4000 failed completely and became gummy during the fifth year of testing

mikeracca · Mar 26, 2022

jssailem said:
Be advised that 3M 4000UV has experienced failure.

3M UV4000 failed completely and became gummy during the fifth year of testing

When I started sealing Lilly, I was told the same thing, so I stayed away from the 4000. The 4200 isn’t the same stuff and so far so good with it. I plan on sealing Luna with it this summer.

jdrutten · Mar 26, 2022

I've got a coil of Bed-It Butyl Tape that I bought last season and will be using in the upcoming weeks to rebed various hardware on my boat. I'm still a bit unsure of this approach though, since my Hunter uses embedded aluminum plates for the stanchions instead of traditional backing plates or washers (handrails, sail tracks, etc. use washers). That is, there's no nut to tighten under the deck, and the bolt is simply tightened at the head. I'm considering using some form of caulk at the stanchions instead of the butyl tape, since a fluid caulk should be less affected by the twisting during tightening of the bolt head. Practical Sailor recommends Sudbury Elastomeric Sealant, as well as BoatLife Lifeseal for bedding purposes (Marine Sealant Adhesion Tests - Practical Sailor (practical-sailor.com) ).

Scott B · Mar 26, 2022

jdrutten said:
I've got a coil of Bed-It Butyl Tape that I bought last season and will be using in the upcoming weeks to rebed various hardware on my boat. I'm still a bit unsure of this approach though, since my Hunter uses embedded aluminum plates for the stanchions instead of traditional backing plates or washers (handrails, sail tracks, etc. use washers). That is, there's no nut to tighten under the deck, and the bolt is simply tightened at the head. I'm considering using some form of caulk at the stanchions instead of the butyl tape, since a fluid caulk should be less affected by the twisting during tightening of the bolt head. Practical Sailor recommends Sudbury Elastomeric Sealant, as well as BoatLife Lifeseal for bedding purposes (Marine Sealant Adhesion Tests - Practical Sailor (practical-sailor.com) ).

Here's good information on Bed-it. It is different than standard butyl mentioned in the PS article.

Bedding Deck Hardware With Bed-IT Tape - Marine How To

Originally published December 2003 *Moved & Edited September 2017 Bedding With Bed-It Tape 5/20/2022 IMPORTANT UPDATE BED-IT TAPE IS BACK PURCHASE BED-IT TAPE Countersunk/Beveled Hole Over the years,

marinehowto.com

jssailem · Mar 26, 2022

jdrutten said:
the bolt is simply tightened at the head.

Yes. Use of Bed-It may not be the best option. The advantage of Bed-It, in my opinion, is in the nature of the product. It is a rubber base that when placed between two mechanical surfaces spreads between the surface, adheres to both surfaces, remains flexible, and releases with manual force without harming either surface.

When using a mechanical screw into a fixed surface, you compromise (too some extent) the ability for the material to adhere to one of the surfaces. This is a problem especially if the temps are low. You are better off using a caulk that is more of a fluid state (like 4200) around the screws. You could make a dam of the Bed-It around the flat base surface of the stanchion. When you screw in the bolts, they will compress the Bed-It between the surfaces (deck and stanchion base) providing extra element to inhibit water intrusion. It is a bit of overkill, but considering water maybe of value.

Sealing Deck Fittings

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SBO Weather and Forecasting Forum Jim & John

SBO Weather and Forecasting Forum Jim & John

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SBO Weather and Forecasting Forum Jim & John

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SBO Weather and Forecasting Forum Jim & John