01 outback tripping ignition breaker

i started boat up and it starts and runs perfect then it just shuts off in about two minutes. the breaker near the key trips. Wait a bit reset and it starts fine and repeats. the two wires in and out of the breaker get hot. the purple wire in the key (ignition)gets hot also. so i looked for wires getting hot on the engine side and came across the purple wire on the oil pressure switch was hot. looked into this a bit further and seemed as though the switch was bad. replaced with new one and the problem persists. is it possible that the new switch is bad? or do i have some other problem going on. on a side note if i unplug the purple wire from the oil pressure fuel shutoff switch the boat runs fine for a lot longer but i think it eventually runs out of fuel but none of the wires get hot. this is also leading me to believe that the new switch may be bad. Thanks in advance for any and all replies.