I want to seal the hole where wires enter in my mast. Every time it rains or there is a lot of spray, water drips into the wheelhouse where the clump of wires exit. What is the best way to go about this?
I took a hole saw to some plywood which gave me a round plug, then I wrapped it in shipping tape and waxed it. I used this to mold a small fiberglass cylinder, which I put into the canopy so that the entry hole stood a little proud of the canopy surface. This cylinder fits into the hole on the radar mast. I haven't tried this out yet as my boat is yet to see water, but it seemed to make sense to me.
A pad and a small coaming piece like shown above works good for the mounting. At the mast/radar mount I use a grommet for wire protection with a glob of clear silicone. Having an exit point at the bottom of the mast is also important.
I did the same as SeaKarma except i used a piece of PVC and stood it up 3 " through and a 1/4" hole in the aft of my mast. Never had a problem.
If you can loop the wires in such a way as to make a drip loop with a low point that is not over the hole in your roof it might help. Simple as pulling back some slack and arranging it so the water drips where you want it to as it runs down the wires.
You could try something like this https://www.amazon.com/Blue-Sea-Sys...-4&keywords=waterproof+wire+pass+through&th=1
Quick and easy would be to pull some slack in all those cables so the water would not run right down the cables and into the mast. Then cover the the hole with a clam shell cover.
You definitely need to pull some slack back on those wires and make a drip loop too. A few have said it but here is a pic of what we mean just in case. Rain or spray will run down the wires from the radar and then have to drip off because the wires will then run uphill into the clamshell/hole.
Thanks guys, very helpful. Will make a drip loop and add a clamshell plate with silicon. Hoping should do the trick.