Wiring E-bilge pump question

After 3 or 4 years, wire connections for the electric bilge have rotted out. There’s nothing left of the wire connection other than green residue. They were always wet, mostly with salt water.

The connections were soldered, then covered with several coats of West Marine liquid electrical tape, which the label says “seals and protects electrical connections.” I think it didn’t seal well to the plastic jacket of the wire, and water intruded between the jacket and the liquid tape material. That’s just a theory based on how easily I was able to separate the tape from the wire jacket.

What is the best practice for protecting electrial connections you know are going to be wet?



– Last Updated: Oct-04-15 12:09 AM EST –

I can believe that there was insufficient adherence to the insulation. Bonding ANYTHING to most types of plastic is very difficult. This is why paint for most plastics works so terribly. I put silicone calk over some connections, but not directly on bare contacts. I also wash everything with soapy water when in salt. I don't know if the calk is any better than the liquid electrical tape. I also don't know how much heat it can tolerate. I've never used it with high current draw. It might burn if it gets too hot. Maybe someone else can speak to this. I fully expect that the caulk will degrade, and use more when needed. By the way, silicone caulk is used for salt water aquarium construction. It seems like the main cause of degradation is mechanical stress.

Dear Unconnected

– Last Updated: Oct-03-15 3:22 PM EST –

where are the 'connections' ?

in a waterproof box ? Pelican, Otter, sturdy bag ?

control wires run into the box, connect, then run out to ?

photo's using wire insulation to inexpensive adhesive... prob on the JB Weld level relative to more sophisticated chemistry... to nylon fittings used for box or bag entry.

Nylon and wire coatings have a difficult reputation yet first try here was sound and stable waaay beyond reasonable expected stresses

The environment for the fittings is in cockpit and relatively dry. 3M Marine adhesives...4000, 5000...could be more water resistant but first off slightly less pull stress tolerant.

If avoiding jumping up and down on the fittings there would be naught problema.

If connections are on a switch where boxing is difficult then pot switch with you know...Gflex...or 3M or Loctite adhesive.

find a plastic container...try Miscount Autoparts.

small parts pack in a small transparent container.

Chose a sizable container, throw the parts in the can, place switch into container with wires and flood with epoxy et al.

DIY Box !

I pot with liquid tape from Grainger's...relay potting.

LT photo's as we're on site:


No, these fittings were not long term tested immersed in salt water. Rainwater, salt water moisture.

hydrophone is a: http://mineroff-nature.com/nature/smemhsii-hydrophone-microphone-system-p-193.html

If necessary, run wire connection thru a nylon tube before terminalizing the ends then pot the tube.

Ignore “datakoll”, it’s an annoying spambot. I just remembered having come across this at some point:


It deals with waterproofing motors using “Sugru”. This might work, though I’ve never used it.