Truly watertight electrical connection

Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
While making a passage from Galveston to Tampa Bay in our Beneteau Oceanis 37; We spent 4.5 days in a storm that was up to force 8. The factory wire connection to our R&D navigation lights located in the anchor locker parted due to corrosion and we had to sail 3 nights without the R&G.
The connection was crimp with shrink tube, one wire to two wires. The shrink tube could not totally prevent the ingress of saltwater between the two wire exit.
During my sleep deprived period at the helm; My mind pondered on ways to guarantee a truly watertight connection.
This is what I came up with. Make a crimped connection like normal but next use an oversize shrink tube and shrink on end slightly so it can slide over the wire. Slide it up to the connection. Fill the tube with Life Seal and slide the tube over the connection or connections. The life seal squeezes up around the connection. If you want you can add more Life Seal. Now shrink the other end. You can knead the Life Seal in the tube if you choose. Now slowly shrink the rest of the tube. Life Seal will ooze out each end. Stop at that point. You can shrink the ends tight if you want. You will notice where multiple wires exit your connection the Life Seal has completely sealed all the gaps.
Let cure and you have a truly watertight joint.
I took a pic of some samples but don,t know yet if I can upload it. It should be attached.
20161218_151844.jpg

Note: If you want a neater appearance you can take a shrink tube just large enough to fit over your shrunk ends and shrink it down giving a very professional appearance. It doesn't matter if the Seal cures inside the connection though I'm pretty sure over time it will like in your tube. LOL.
You may already know this method but no-one on my dock had.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Great minds think alike. Course sleep deprivation and fear for your life can significantly enhance the process time wise.....
https://www.amazon.com/Connectors-S...d=1482100676&sr=8-1&keywords=waterproof+crimp

I'm going to put your solution in my haversack of "stuff you can do while on a long passage to actually fix a problem and not have to fix it later while on the hook" There are so many things that you can do to get you through a passage that are not real fixes because you need that special piece.
 
  • Like
Likes: Pilgrimtex
Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
Great info. They are in my elect. Box. But what do you do when you have two wires coming off one end such as power side to two navigation lights. That's where the beauty of this fix really shines out.
 
Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
I used to design and build manufacturing machines and some process machines we're for use in explosion proof areas. All electrical connections had to be "potted" which was filled with a compound to prevent the ingress of fumes such as MEK.
Adhesive lined shrink connectors cannot guarantee a seal if you have two wires coming off a crimp. This approach is a form of "potting". You can also seal a bundle of connectors if your shrink tubing is large enough. Notice the photo where multiple wires exit the connection.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
thats what they make dielectric grease for.
its a waterproof silicone grease that they have been using it in underground waterproof fiberoptic splices for years.

to make the connection for the type of wires we are dealing with, after stripping the end of the wire, dip it in the grease before slipping it into the connector.... then crimp it. do the same for the wire on the other side of the terminal....
as the terminal is crimped, the grease will displace the air in the terminal, and NOT allow water in... heat shink over it is redundent but does strengthen the splice and help preserve the water tightness for many years.

I have posted this same thing here several times when someone was looking for a simple way to insure a waterproof connection for their wires.... splicing bilge pump wires that are too short is a prime example of needing a truly watertight splice.

but a good adhesive heat shrink tube, properly applied to a twin wire could also create a waterproof seal if the wire is cleaned good before the application, and a slight pressure is applied to the shrunk down tube (while its still very warm) where the wire exits from it, to squeeze the adhesive in to the groove of the wire.
 
Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
I have a much greater appreciation for my Beneteau. I would much rather have gone through a full blown tropical storm than what we got caught in. The storm started as a tropical depression off the east coast of Florida. It decided to cross west over Florida into the northern Gulf. Once in the Gulf it fed off the warm water and morphed into a monster that stretched almost to Texas.
We were sailing northeast from the 27th parallel to miss the heavy traffic off New Orleans and then head southeast into Tampa Bay. We had been in touch with a chemical tanker just the day before and he gave us a weather report that supported our course. He agreed that our plan was good.
We got into the worst of it off New Orleans midway to Florida. I have Sirius weather and could see the storm. It also gives me access to weather buoys and their information.
The storm was like clusters of cells. Wind shifts were constant and the seas were all mixed up like in the eye of a hurricane. Winds were up to 40 knots from all directions. 50 knot wind barbs were plastered on the chartplotter. Seas were 4-5 meter, very steep. Waves crashed over the cabin and into the cockpit through our canvass. Waves came in the transom and up to 6" deep at my feet.
I have a completely rigged sea anchor and bridal system but couldn't use it because of the wind shifts.
My sail bags lashed to the bow pulpit broke loose and we're sliding all over the deck. The bow roller loosened slightlyfrom the deck from the pounding.
The wind and waves blew the bearing balls out of my boom car and slid the track about 12 inches toward the mast.
We pumped about 20 gallons of seawater out of the bilge. I joked and said we aged the boat 20 years from the pounding she took.
All in all we learned a lot. I hope not to tackle a storm like this again but looking back glad we did. Gave us quite an education.
Treva's sisters contacted the coast guard and they pinged her cell phone and our AIS transponder. It showed us off Sanibel Island.
 
Last edited:

Gunni

.
Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
I assume that you have two bow nav lights. I would do away with any connections in the anchor locker due to the wet corrosive environment. Place a marine junction box inside the boat and run separate wire to each fixture. I carry two types of battery powered nav lights for just this kind of scenario. I also pull my 70# anchor from the roller and lash it inside the anchor locker in storm conditions.
 
Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
Thanks for the tips Gunni. I plan to place a tricolor on the masthead as well for redundancy and high seas. I'll check to see if my 55# Mantus will fit in the locker. Been thinking of ways to secure it better. Beneteau pulpit is not that strong for a pulpit mount.
By the way, I didn't loose my two sails thank goodness.
 
May 17, 2004
5,031
Beneteau Oceanis 37 Havre de Grace
Beneteau pulpit is not that strong for a pulpit mount
Good story. I remember you taking delivery of your 37 just a couple months after we got ours.

One thing I noticed on our 37 is that the bow roller was held down by three bolts through the hull, but one of the aft bolts (which probably take a lot of the torque when under load) had its washer only half on the hull (pic below). If yours was put together the same that could explain some of the weakness. Our dealer came back and shimmed some starboard between the washer and the deck, but who knows if putting the force on the deck would really be any better if it's meant to be on the hull.

By the way, where did the 20 gallons of water come from?

IMG_2470.JPG
 
Oct 13, 2013
129
Beneteau 37 Oceanis Platinum Edition Seabrook, TX
Great info. Davidasailor. I had the bow roller extended 7 inches to fit my Mantus anchor which didn't help. I'm thinking of making a plate and glassing it in place.
I'm not sure where all the water came from. Two locations are the coming covering the cabin entrance couldn't handle green water flooding the cabin top yet there was no evidence inside of leaks. The other is the access hatch at the stern which to me is not adequate and we had waves ingressing through the opening to the swim platform which put that hatch underwater. That same type hatch was responsible for my friends bay fishing boat sinking at the dock from waves lapping on the flatdeck.
I'm looking at replacing it down the road with one that will definitely seal the opening. One item of my new list since the passage.