200hp Mercury electrical problem

by brian botelho
(kerman ca)

200hp engine blew on my 1999 nitro boat. I found a used 200hp on a wrecked boat. I switched them out and took the boat out. Had to end up switching out the prop as well. All looked and sounded good at home but when I put the boat in the water and started it up, it ran for maybe 5 -10 mins then shut down. It's more of an electrical problem because the engine isn't stalling out. It just shuts off and when I go to restart the engine, there's nothing. No electricity getting to anything. Wait about 15 mins and it starts up then the same thing happens again. Any suggestions as to where I should start?