shore power dead short

[dean price]

after a rough time on the water sat and taking on alot of spray etc. i anchored overnite and returned to my slip sun.. when i plugged in on the dockside it threw the docks 15 amp breaker. i hadn't had trouble before. i checked the breaker box on board and found it to be wet inside.(1973 f-31) so i sprayed wd 40 inside the box and let it dry overnite. today it still trips the breaker. i shut off the 4 acc breakers, port side, starbrd side, hot water and stove to isolate the main. still tripped. checked the ohms with main open and two read "0"and the third was ".4" . i am a novice about electricity . anyone have any ideas ? thanks dean

[g36]

i dont about your f-31. i have an f-32, but could your shore/gen switch have also gotten wet?
if all of your branch circuits are off and only the main is on your should be able to isolate this problem. does it trip with just the main on or is it tripping when it is off also?
have you checked to see if your electrical connection at the boat or maybe your shore power cord is wet also?

[dean price]

i don't have a gen and it flips the dock breaker if the main is off or on. interestingly the ohms reading on 1 of the 3 main breakers is now 1 . i also switched power cords. still stumped , maybe its time to change the 35 year old breakers.

[jwrape]

I have a F44 and Never had it wet but once when i got a short, it ended up being a small short wire behind the Shore to Gen power switch that was burnt.
If you got it wet, it might have arched and burnt.
Pull the panel and look around. I looked at it twice before my Dad finally found it tucked under that switch.

[Buckknekkid]

I had the same issue with the rotary switch, it was careless tightening of a scrw on the switch allowing the wire to touch the next. Check every connection