Making watertight Splice in Humid bilge area environment

[jstevens]

I haven't used these connectors for on board wiring, so I can't provide any experience with them, but I would consider something on this order for electrical connections that must be made in humid (e.g., bilge) or hot (e.g., engine compartment) locations.
https://www.delcity.net/store/Deutsc...ctors/p_822961

They are used in the automotive industry. They are a PITA to set up, but they do provide a secure, sealed connection that can be disconnected.

John

[David M]

I use the Ancor butt connectors that come with the built in heatshrink. You just have to be careful to not crimp it so hard that the heatshrink is cut all the way through.

https://www.google.com/search?q=anco...=2102&bih=1442

[toddster8]

As it happens, I had to replace a worn-out float switch a couple of weeks ago. Although the old splices down in the bilge - heat shrink over twisted wire, then a wad of tape - had not failed, I couldn't bring myself to replicate that nasty mess. (How long has it been since they sold mercury float switches, anyway?)
The pump is in a sump directly below the engine, so I went straight up through the sole to a new terminal strip, high and dry in the engine compartment. Of course, this probably worked because my boat is relatively small. I still prefer to have a mechanical disconnect for any installed equipment.

[UNCIVILIZED]

I don't have the reference pub's handy, but I think that ABYC guidelines give soldered connections a thumbs down. At least as far as standard wiring. Though if someone knows for certain...

[P3sailor]

I've used "environmental" splices in the past. They're a crimp style splice and after crimping a heat gun is used to shrink the sleeve which also has a wax like substance on the inside which melts and seals the splice. Works very well, not sure what range of wire sizes are available or the name of the product. Also, have you tried any of the self-vulcanizing tapes that are available. A little goes a long way and if applied correctly may work for you. Otherwise do your splice and seal with RTV, an old standby.

[skipmac]

Here is another argument that I think is strongly in favor of crimp only, no solder.

I purchased an Ultra bilge pump switch (considered by many to be the best, most reliable switch you can get). It comes with heat shrink crimp connectors installed on the wires coming from the switch. The instructions state clearly that the pump warranty will be voided if those connectors are removed or if you use any method of installation other than crimping and heat shrinking the wires to your boat's system.

[zboss]

Water tight junction boxes containing properly terminated heat shrink connections to a bus bar and treated liberally with anti-corrosive as needed.

[Colin A]

Best bet is a heat shrink crimp and getting it as high as possible. I know some people will also add another layer of heat shrink as well.

[Colin A]

Originally Posted by UNCIVILIZED

I don't have the reference pub's handy, but I think that ABYC guidelines give soldered connections a thumbs down. At least as far as standard wiring. Though if someone knows for certain...

Solder can't be the only method but it can be used. For instance you can use an uninsulated crimp then solder after crimping then cover with heatshrink.

[stnick]

As a Phone lineman splicing 22 gage wire fast was RED scotch locks 3 M Dialectric greese around crinp connector semi clear so you can see crimped wires. Than a splice kit was applied T banana shaped tube of red grease to water proof . Many lasted 20 years !

[Bigapple1]

I appreciate the quick response and all the ideas from forum members. I'm sure this topic can be of value to many.


I decided to take the following approach for the fall, and review all the wiring for my bilge pumps over the winter (I have two identical automatic bilge pumps. One located 3 inches higher than the other one for redundancy)

1. Ditched the use of any electrical or wrapping type tape. I stripped the damaged wire splice, slid on a somewhat longer heat shrink tube, made sure I used the correctly sized butt connector, and crimped it.
   I did solder the crimped connector (I've never had any issues with both crimped and solder connection) – note that the failure was corrosion/breaking of the copper wire outside of the connector – not inside the butt splice
2. I then shrunk the sleeving. Althought the shrink sleeving did look like it was tight around the wire, I purchased and applied Liquid Electrical Tape over the joints where the shrink sleeve meets the wire jacket – to try and prevent moisture from entering the shrink joint.
   In the spring will inspect this repair to see if LET is still bonding to the shrink sleeve and wire jacket.
3. Since the area where the splice failed was near to where the bilge wires are secured, and routed across an engine bed 'timber' at the front of the engine, I also decided to add more clamps to better secure the bilge pump wiring, in the event that engine movement and vibration may have been causing some flexing of the lead(s) - to failure.

[ramblinrod]

In my experience, about 90% of rec boats have substandard bilge pump capacity, installation, and wiring.

This may be THE most important safety device on the boat, and often receives the least attention.

(BTW, VHF radios, arguably the second most important safety device, are the second most likely device to have substandard wiring.)

ABYC sets the absolute minimum standard anyone should consider, and in my opinion, only sets a reasonable standard to help prevent electrical fire.

A soldered wire splice can be very reliable if it comes from the hands of a very skilled electrical or electronic technician.

The trouble is:

a) There are few who are sufficiently skilled at making reliable soldered wire splices.
b) Some who believe they are, aren't.
c) Quality control verification is trickier than, "If there is a current calibration sticker on the crimpers used, all is well" (which isn't true but standards associations tend to turn a blind eye to this).

So here is my recommendation for y'all.

1. If at all possible, get the bilge pump connections up and out of the bilge, above the height of the battery terminals that power the bilge pump.

(The battery then becomes the lowest point that causes bilge pump failure due to flooding, and when that happens, the vessel is most definitely going down.)

2. If that is not possible, use a waterproof plastic electrical box with water-tight cable glands.

3. Use crimped ring connectors on a terminal strip.

4. Follow ABYC (or applicable authority for your jurisdiction) standards to the freakin' letter for cable size and over-current protection.

5. Evaluate your bilge pump capacity. I recommend 3000 GPH min, and at least 1000 GPH minimum for each 10 ft of boat length, split over at least 3 electric pumps.

6. Follow the pump manufacturer's recommendations for suction and discharge hose plumbing to the letter, minimizing flow resistance where ever possible.

7. Ensure a high water level alarm is installed.

8. Cover all bilge pump and high water alarm terminal strip electrical connections completely, with a generous amount of silicone sealant.

9. Keep the bilge spotless. (Many bilge pump failures are due to lodged debris.)

10. If you are not skilled with making reliable electrical connections that you are 100% confident will work when your life depends on it, whether that should be today or 10 years from now, hire a "sparky" that comes highly recommended by very experienced sailors.

11. Test bilge pumps frequently (and flow rate at least annually) to verify they are working properly.

12. If your boat springs a leak:

Step 1. Turn on all pumps.

Step 2. Start the engine (to achieve maximum pump capacity based on alternator charge voltage).

Step 3. Find the leak and stop it.

Step 4. If step 3 cannot be completed well before the water rises above the batteries, call a May Day.

Step 5. Trigger the Epirb, PLB, and liferaft.

Step 6. Grab the ditch kit and abandon ship at the last possible moment.

(Steps 1 and 2 will give you the maximum amount of time possible to complete additional steps as necessary.)

[ramblinrod]

Originally Posted by toddster8

As it happens, I had to replace a worn-out float switch a couple of weeks ago. Although the old splices down in the bilge - heat shrink over twisted wire, then a wad of tape - had not failed, I couldn't bring myself to replicate that nasty mess. (How long has it been since they sold mercury float switches, anyway?)
The pump is in a sump directly below the engine, so I went straight up through the sole to a new terminal strip, high and dry in the engine compartment. Of course, this probably worked because my boat is relatively small. I still prefer to have a mechanical disconnect for any installed equipment.

Thank you for sharing your installation photo.

One of the better DIY installations I've seen, and likely better than on the 75% of the boats owned by those following this thread.

Issues:

1. Never put wiring in an engine compartment that doesn't have to be.

a) Seawater cooling system leak and it could be doused with water.
b) Engine compartment fire and it could go up in smoke.
c) Catastrophic engine failure and it could be smashed by flying parts.

(During all of these scenarios, you may really need your bilge pump to work.)

2. Lack of chafe protection on the wires going through the fibreglass holes.

(FRP will completely dull a high quality jig saw blade after cutting about 6" through 6 mm laminate; imagine what the jagged edge of a hole drilled in FRP will do to the insulation on that cable.)

3. Terminal strip connections are suspected to be below the height of the battery terminals and are not waterproof.

[mowerandy]

Your bilge sounds just like mine. I used to solder the bilge-pump connections, but on untinned wire (both boat and pump wires in my case) it just causes electrolytic corrosion of the copper and fails the joint in 2-3 seasons. If you just tightly twist the clean copper wires together on the other hand, and then wrap in a couple of turns of self-amalgamating tape to seal then it will be good for longer than the bilge pump!

[mitiempo]

Originally Posted by Colin A

Solder can't be the only method but it can be used. For instance you can use an uninsulated crimp then solder after crimping then cover with heatshrink.

If the crimp is a proper one the only addition after soldering is a hard spot at the end of the solder.

Here is a link to just about all you need to know about wire termination:

Marine Wire Termination Photo Gallery by Compass Marine How To at pbase.com