Moderated Discussion Areas
  ContinuousWave: Small Boat Electrical
  Water-resistant Wire Splices

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   Water-resistant Wire Splices
Frank O posted 08-29-2006 03:42 PM ET (US)   Profile for Frank O   Send Email to Frank O  
If it turns out that I need to replace my bilge pump or float switch, I'd prefer to be able to splice the wires relatively close to (within a couple of feet of) the pump or switch. Which then raises the question: is there a way of making such a wire splice sufficiently waterproof?
davej14 posted 08-29-2006 05:17 PM ET (US)     Profile for davej14  Send Email to davej14     
Use Anchor crimp splices with heat shrink. These splices have an adhesive coating inside the heat shrink that will seal to the wire when they are heated. After crimping you can use the heat from a soldering iron to shrink the tubing, just keep it moving and be careful not to burn it. Once it is done you will see the adhesive forced out slightly on each end of the splice.
Frank O posted 08-29-2006 05:34 PM ET (US)     Profile for Frank O  Send Email to Frank O     
Thanks. I'll take a wild guess and wager that that's what the West Marine website calls Ancor Waterproof Butt Connectors -- "adhesive-lined heat shrink connectors [that] are ideal for bilge pump and switch leads or any area exposed to moisture."

Casco Bay Outrage posted 08-29-2006 07:13 PM ET (US)     Profile for Casco Bay Outrage  Send Email to Casco Bay Outrage     
In addition, you can add a coating of liquid electrical tape.
This is great for adding an additional layer of protection.
cwolf posted 08-29-2006 07:34 PM ET (US)     Profile for cwolf  Send Email to cwolf     
One comment on the Anchor heat shrink connectors, although I really like the ease of use I still find that when crimping the plastic liner can be compromised. I still use them but for a bilge application I would opt to use the Anchor heat shrink tubing over the connector.
jimh posted 08-29-2006 07:40 PM ET (US)     Profile for jimh  Send Email to jimh     
When installing a switch or pump which may be operated submerged in some conditions, I recommend avoiding having any splices or connections which will be below the water, if at all possible. Usually the replacement pump or switch will have long leads, just like the original.

When making the original installation or updating an existing installation, I recommend you make all the connections between the pump and the float switch as far above the anticipated waterline as possible.

Making a splice which will be subjected to immersion is not a good plan for an electrical installation.

Frank O posted 08-29-2006 11:05 PM ET (US)     Profile for Frank O  Send Email to Frank O     
Thanks to all for the advice, sounds good. Jim, I understand the premise that the best approach would be to avoid water contact with electrical splices. The only way I can see doing this when replacing my bilge pump would be to:

-- disconnect the wire connections at the console end and attach the wires to a sturdy line;

-- pull the wires out from the bilge end, remove old pump and wires, splice in new pump/wires leaving the wires long;

-- pull the wires back through from the console end via the sturdy line; reattach wire connections.

Is that about what would be called for, or is there an easier way to skin this cat?

jimh posted 08-30-2006 12:12 AM ET (US)     Profile for jimh  Send Email to jimh     
I left all the wires on the switch and pump as long as possible. I led them upward, away from the low point of the sump, and made all the interconnections above the sump.
Chuck Tribolet posted 08-30-2006 09:32 AM ET (US)     Profile for Chuck Tribolet  Send Email to Chuck Tribolet     
In the bilge: solder, then a nice long piece of the Ancor
hot melt glue lined heat shrink. Be sure to put the tubing
on the wire before you solder (DUH, but the voice of
experience) and keep the tubing well away from the solder
joint until it's cool (DUH, but the voice of experience).

Then place the joints so they aren't laying in the residual
water in the bilge.


davej14 posted 08-30-2006 12:46 PM ET (US)     Profile for davej14  Send Email to davej14     
The crimp connection will be fine, just be sure to use a crimping tool that is designed for insulated connectors. This tool does not have the sharp "nub" that is on the tool used for uninsulated crimps and it will not pierce the insulation. I usually stagger the connections.

Why not just pull the new wires through the tunnel with the old ones and save the intermediate step? You could temporarily solder them together and tape over the splice to give you a smooth continuous surface to pull through the tunnel.

andygere posted 08-31-2006 02:25 PM ET (US)     Profile for andygere  Send Email to andygere     
The last bilge pump and switch I purchased (Rule brand) had woefully short leads on both, less than 24 inches. On an Outrage 22, this is not nearly enough length to get the splice into a dry location. The wiring from the factory installed pump switch runs through the rigging tunnel, and I regard the entire tunnel as a wet area. The wires do not need to be continuously sumberged in order for a leaky splice to deteriorate quickly.

I suspect the high price of copper is one reason for the inadequate length of these leads on new pumps and float switches. For these applications, I've had good luck with the Anchor waterproof splices, backed up with either glue-lined heat shrink tubing or a generous coating of liquid electrical tape.

knothead posted 08-31-2006 06:30 PM ET (US)     Profile for knothead  Send Email to knothead     
Frank O,

I connected my Rule bilge pump with Ancor heat shrink butt connections, then covered the connection with Ancor heat shrink tubing. I've had no problems for 5 years.

The boat is a Montauk and stays in a salt water slip for 2 months during the summer.


davej14 posted 08-31-2006 08:32 PM ET (US)     Profile for davej14  Send Email to davej14     
The ultimate splice would be a heat shrink insulated crimp splice preloaded with "gel". "Gel" material actually displaces water and would permanently protect the splice from attack. The heat shrink would add an additional moisture barrier and provide mechanical support. There are now wire nuts preloaded with "gel" rated for direct burial but they are not suitable for marine applications. Someone needs to invent this product.
Mumbo Jumbo posted 09-07-2006 11:24 AM ET (US)     Profile for Mumbo Jumbo  Send Email to Mumbo Jumbo     
The best procedure is outlined by Chuck Tribolet: a good, soldered mechanical connection covered with Ancor adhesive lined heatshrink tubing.
l_anthony posted 05-26-2008 08:28 PM ET (US)     Profile for l_anthony  Send Email to l_anthony     
I am rebuilding a classic Land N Sea houseboat. I am putting a Rule 2000 with a Rule auto-switch in. The leads are short on this. I have a Rule 3500 as well I am planning on putting this up front for an emergency. The [Rule 3500] has long leads. Installing the switch is forcing me to put two wires into one side of my splice, the positive coupled with one of the leads from the auto-switch. This will be hard to waterproof two wires coming out of one end of my splice? Any suggestions here?



seabob4 posted 05-26-2008 08:37 PM ET (US)     Profile for seabob4  Send Email to seabob4     
Very simple. 14-16 GA uninsulated butt splice, twist both wires coming off the float and your pump together, a 1 1/2" length of adhesive lined heat shrink, splice to the brown wire coming from the helm, crimp, and shrink. ALWAYS elevate the wiring coming out of the switch and the pump before securing. There is a reason bilge pump and float switch wiring exits out of the top of their housings!
Chuck Tribolet posted 05-27-2008 08:59 PM ET (US)     Profile for Chuck Tribolet  Send Email to Chuck Tribolet     
Seabob: the problem with that is that your aren't guaranteed
that there's enough glue to fill the gap between the two

And I'd go a LOT longer than 1.5" on the heat shrink.

l_anthony: on the Rule 2000 with short leads: extend the lead
1:1, then make the 2:1 connection well above reasonable water
level, and point the 2 side down. Maybe even run the wires
ALL the way back to the switch.


aja posted 05-28-2008 08:35 AM ET (US)     Profile for aja  Send Email to aja     
In a previous life where I used to work on well water systems. A similar connection we would frequently make up were between the leads of a submersible pump and the wires running down the well. These motors most often operated on 220V single phase power so had 3 leads to connect, and were designed to be submerged under hundreds of feet of water for many years. The "kits" which came with the pumps included uninsulated butt splice crimp lugs with adhesive lined heat shrink tubing for each wire lead.
These were easy to make up and I can't think of a case in the couple of years I was doing that work where a pump had to be pulled due to the faulure of one of these connections.

sternorama posted 05-28-2008 12:52 PM ET (US)     Profile for sternorama  Send Email to sternorama     
Those salt water well drinkers are a tough crowd! ;)
L H G posted 05-28-2008 04:39 PM ET (US)     Profile for L H G    
For a REALLY WATERTIGHT, non-Kosher connection, I use a method told to me by Clark Roberts. I made an emergency Bilge pump float switch repair this way five years ago, almost always under water, and still working fine.

Use a correctly sized plastic wire-nut. Twist the two (or more) wires together and screw on the wire-nut. Then fill the wire-nut flush with marine silicone caulking, let cure. Your problems will be over. This also works well for any trailer light connections.

Chuck Tribolet posted 05-28-2008 08:49 PM ET (US)     Profile for Chuck Tribolet  Send Email to Chuck Tribolet     
l_anthony: Upon further reflection, I'd do a 1:1 splice with
solder and hot-melt-glue-lined-heatshrink to extend the wires
well out of the bilge (e.g., into the console).


jimh posted 05-28-2008 09:32 PM ET (US)     Profile for jimh  Send Email to jimh     
I hesitate to recommend any use of a sealant like silicon caulk (RTV) on electrical circuits because many of those compounds leech acetic acid as they cure. Acetic acid and copper wire are not good combinations. There are some grades of RTV that are marked as non-corrosive. These might be better as a sealant for electrical components.
alfred posted 05-29-2008 07:52 AM ET (US)     Profile for alfred  Send Email to alfred     
I installed a Rule auto pump over a year ago and it came with short leads as well. I soldered the wires and covered with the heat shrink tube with glue on the inside with about 2inches overlap either side of the joint, then again with a larger diameter heat shrink with glue, this time with 3 inches of overlap from the joint. So far it has held up well.

This approach takes a little planning as you need to get the 2 sets tubes over the wires before they are joined.

I used a heat gun to shrink the tubing, making sure that tube was heated from all directions. I used a wet cloth to shield the second set of tubes, when shrinking the first.

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.