Sealing electrical connections?

nola mike

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End of the season storm last year hit my boat lift. All connections are enclosed, and nothing was submerged, but I guess that salt spray is pretty pervasive. Many connections corroded/broke. I'd like to make them more water resistant. They were shrink wrapped and liquid taped. I'm thinking I just need to completely isolate the connections. A giant glob of grease on everything would probably be fairly effective but not that elegant. Same with slathering everything with some kind of caulk. Better ideas? This article I found was pretty good; looks like maybe the CRC HD would be suitable for this application.
 

froggy1150

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Look at gel splices. They make a bazillion (not really) they have them from 22 guage telecom to big industrial line power taps
 

04fxdwgi25

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I would be soldering and using sealing shrink tube, the stuff with the glue in it.

For regular connections, I lightly coat everything with No-Ox_ID conductive grease. Telecom companies use it on all -48 VDC buss cables and connections.

I use it on all connections on vehicles, boats, battery terminal connections and trailers and never have corrosion problems.

 

Scott Danforth

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which connections?

for battery connections, simply use marine electrical varnish (available from McMaster Carr as well as your local grainger or electrical house)

for soldered connections, always use the adhesive lined shrink wrap.

for any removable connection, the Deutsch DT series of connectors
 

Chris1956

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There are marine grade butt connectors, with shrinking, adhesive lined insulators. With the right crimping tool, and a heat gun they are waterproof.

The low tech solution is wire nuts with silicone caulk.

For all connections, it is imperative that no water collects around them, or it will find a way.
 

dingbat

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unfortunately, most boat OEMs in the 80's, 90's, and even the 00's didnt use tinned wire.
And Iā€™m sure a number of ā€œfreshwaterā€ builders still use untinned wire as a cost saving measure. Use 304 instead of 316 hardware as well.

Most cable/wires are PVC jacketed. As such, youā€™re looking at a life expectancy of 20 -25 years before the jacket hardends and wires start to get brittle.

If your dealing with 50-60 yro wiring, it should be replaced for integrity purposes
 

Grub54891

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There are marine grade butt connectors, with shrinking, adhesive lined insulators. With the right crimping tool, and a heat gun they are waterproof.

The low tech solution is wire nuts with silicone caulk.

For all connections, it is imperative that no water collects around them, or it will find a way.
ABYC requirements do not allow wire nuts on any boat connections.
 

nola mike

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This is on the lift, not the boat...I have used silicon in the crimps before. My shrink wrap isn't adhesive lined. the lugs used are heavier gauge (4 or 8, don't remember) and bare brass.

EDIT: The problem is water getting in at the far end of the crimp I think. the failure point is where the wire meets the connector. IDK if the adhesive lined wrap will prevent that (I thought that the liquid tape should). The wiring is not tinned--I had read different opinions on that. That ship has sailed though. Wondering if tinning the ends would help. Although that would be a trick to do on the lift in the middle of the water without AC power.
 
Last edited:

dingbat

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This is on the lift, not the boat...I have used silicon in the crimps before. My shrink wrap isn't adhesive lined. the lugs used are heavier gauge (4 or 8, don't remember) and bare brass.

EDIT: The problem is water getting in at the far end of the crimp I think. the failure point is where the wire meets the connector. IDK if the adhesive lined wrap will prevent that (I thought that the liquid tape should). The wiring is not tinned--I had read different opinions on that. That ship has sailed though. Wondering if tinning the ends would help. Although that would be a trick to do on the lift in the middle of the water without AC power.
Good luck tinning a wire after "black wire" disease has settled in.
Once black wire death has set in there is no turning back. It will eventually wick its way from one end of the wire to the other.

Adhesive lined shrink wrap is the only way to go when it comes to sealing wire connections subjected to adverse conditions. Used extensive in buried cable and water well applications. My local plumbing supplier carries a large selection of heavy duty, under ground and under water splice kits

 

Scott Danforth

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Soldering and the adhesive lined shrink wrap will help. Then hose the connection down with 2-3 coats of insulating varnish. It can then be submerged and be OK
 

nola mike

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Soldering and the adhesive lined shrink wrap will help. Then hose the connection down with 2-3 coats of insulating varnish. It can then be submerged and be OK
I'll try this with a mini butane torch. Thinking I'll end up just melting the insulation though. What's the varnish you're talking about? Guessing I won't be able to find it locally. Ordered some new shrink wrap and the crc hd corrosion inhibitor as well.
Good luck tinning a wire after "black wire" disease has settled in.
Once black wire death has set in there is no turning back. It will eventually wick its way from one end of the wire to the other.



I was able to cut the wire back to clean ends, should be ok from that perspective
 

cyclops222

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Post # 8 Is the BEST ADVICE to follow. As many of us have really old reliable boats and motors...... And plastic covered wire and pulley steering systems.

As my best mechanics in the NY area tells me...............
" If it is not worn out. Do not replace it. Oils and antifreezes are the exceptions. " (y)

Dave Nagel Is the best Stock Car and Marine Mechanic in the world. He has saved me 10s of thousands of dollars. On needless PM costs at a marina.
Bless you David. :)
 

cyclops222

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Post # 12 by dingbat is correct about BLACK WIRE conductors. I have run into it a few times. My BATTERY POWERED toys in a damp full basement with RECHARGEABLE batteries would cause it. The batteries were always the run down LIFEPO4 ones. Run down past 0 voltsand some were at -minus .5 vdc. If caught quick enough. Only a foot of wire was removed, and the infected wireand reconnected.
I am rambling today. šŸ˜‹
 
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