Boat quits HELP!!!!

so i have a 1994 sport nautique 351 windsor pro tec efi. so im driving the boat on the trailer and its all fine and then i shut it off and everything quits i didnt even hit the ignition switch all i did was turn the key off so i look at it and it was the circuit breaker but how did it blow right? help!! and then i took it out the weekend after and i hit a big wave and everything quit again so the first thing i looked at was the circuit breaker and of course it was the problem so i clicked it back in then go and push the ignition switch bak in but it wont go in it just kept popping back out so i banged on the dash a couple of times and then it worked again HELP!!! any suggestions???