Trailer wiring - what are your tricks to keep it working

[vartz04]

So I have been fiddling around with this small trailer I got for free

When I got it it had dry rotted 8" tires a bent tongue and no lights or fenders. I plan to make some sides for it at some point

Once I put on some cheap fenders, a new longer tongue, 13" wheels/tires and some lights I just used it for about 6 months to haul my kayak around. During that time I had some issues with the lights and ended up wiring a dedicated ground. Still never worked great. Then I switched to LED lights, better but it still occasionally wouldn't work. I then determined it was the ground pin in the 4 pin plug and also a short in one of the wires. That was the last straw

I took to the internet for ideas. Found one that suggested liquidtight electrical conduit and junction boxes. Seemed like a good idea. I tweaked it a bit.

Now I have 3/4" PVC conduit from the tongue to the frame. Where the 4 pin harness comes out of the conduit it is sealed with marine goop. At the frame there is a standard single gang weatherproof box with a blank cover. This is where each side of the trailer ties together to the main trailer plug. Behind that I put a T conduit body and then liquid tight fittings and conduit down each side of the trailer. At the clearance lights I used another T and then plugged around the wires with marine goop. After the clearance light T it's just a straight shot back to the tail lights and the end of that run of conduit is also plugged around the wire with marine goop.

Basically aside from condensation there is no way for anything to get on my wiring now. We will see how it holds up.

For the wiring I used extension cord from the junction box back. I figure the extra layer of insulation can only help. Every connection is made with heat shrink waterproof crimps and aside from the connections to the tail lights is made inside of a weatherproof box.

Anyone else have good ideas or tricks for trailer wiring ?

 

[vartz04]

That PVC is good albeit a bit overkill, Also a double edge blade... If water does get in, it cant get out either.
I am sort of fussy about my trailer lighting & build everything compatible to SAE J560. Its nice to plug in and go.
Its FAR more robust than any utility trailer or RV grade connector. Never worry or fuss with dodgy wiring or connections. Also, no matter if the car is U.S. or Euro-Japper wiring scheme, its plug and go.

I have considered drilling a hole in the junction box cover that is very small as a vent/drain.

The only problem (and reason I didn't go with) SAE J560 is no car comes standard with that anymore. It's either 4 or 7 or both. Adapters always add another area for failure. I have a company car and sometimes use my wife's car or my inlaws truck and then people borrow the trailer occasionally so this just keeps it easy as nearly everything with a hitch has a 4 pin now.

 

[calicamper]

Ive had a few boat trailers. The small trailers really struggle with grounding. My fix is to run a dedicated ground wire around from tongue down the right side across the rear to the left fender. Then all lights get their grounding mount bolt tied into the ground wire. The ground wire then gets bolted to the tongue. In one case I even tied the tow car ground wire to a ground at the plug pulled off the bolt at the tongue. This cured all my lighting drama problems in every case. No more dark rainy nights in a crummy parking lot fiddling with wires while on a trip.

 

[vartz04]

Ive had a few boat trailers. The small trailers really struggle with grounding. My fix is to run a dedicated ground wire around from tongue down the right side across the rear to the left fender. Then all lights get their grounding mount bolt tied into the ground wire. The ground wire then gets bolted to the tongue. In one case I even tied the tow car ground wire to a ground at the plug pulled off the bolt at the tongue. This cured all my lighting drama problems in every case. No more dark rainy nights in a crummy parking lot fiddling with wires while on a trip.

That parking lot stuff is the exact reason I did all of this. The last time I spent 30 mins in the farm and fleet parking lot an hour from home on my way to a lake in the rain. Ended up buying magnetic tow lights to not ruin the trip

 

[tyler.96]

For any lights, I always run a dedicated ground. I don't rely on using a grounding mount, as rust and paint can prevent good contact. The other half is having as few splices as possible. Every wire nut/butt connector increases the chance for something to go wrong.