Please TEST, because nobody want to read a headline like this: "Sailor get lost...!". Do not riske your life and test it!!!! Stay safe and greatings to the Team

You might want to test that before you go. You basically added insulation to that ECB and it might over heat and damage itself.

Like everyone has said this may lead to overheating of the circuitry. Perhaps using a PlastiKote clear spray might be better in giving the circuitry a thin protective layer.

Some ingredients of that caulk may be electrically conductive, or may become conductive as it ages. Heat dissipation could be an additional concern. The black color could even be CARBON!

No good idea, mate.

This could make the electronics overheat. Can you check it with an infrared camera? Under working conditions, in the sunlight, etc. Hoping for your success, my friend!!! A lot of LG built computer boards have a rubber feeling sealant on them. It is just poured over them in their plastic housings, so many applications will work just fine like this, I just don't know how hot this board gets. No heat sinks visible on it, so it probably doesn't get too hot...

Following you

Hmmmm. I am just a simple electronics engineer and I am not so sure I would have gone down that route as a solution. But I am confident you contacted the manufacturers and got their perspective on this, you have taken great care in all other matters so I hope it works for you. BTW, when are you coming back to Whitehaven? I would like to pop over and meet you, perhaps even give you a hand if I can. Regards. V

Always difficult: be aware that tight container will let vapour water in and condense without possible escape for the liquid...

I've seen transparent silicone being used in ebike battery packs (bms), so I guess it should work.

What is the length of your hull?

Yeah, this is cool, except it will 100% have components that will now overheat and fail. You could trust me, or find out the hard way. If this worked, this is the way your electronics would be made. But they don't make them this way, because many of those little components would overheat.