So I am in desperate need of some advice. I am new here and I have a 25' Sunsation Aggressor with a 502 Magnum MPI in it. Last Sunday I was out with my family for fathers day and she died in the middle of the lake. After getting back to shore, I figured out that the engine is not getting any fuel. I thought the fuel pump relay might be the issue. I pulled the relay and put a jump wire across the terminals and the pump started working again. I brought home the relay and benched tested it and it checks out. So that leads me to the fuse. I am going to check it in the morning. My question is if the fuse is blown, why would it have blown or if its not blown what else could it be?

Its not the fuse because the fuse is inline with the terminals. If it was blown the pump would not have come ON when jumped

How did you determine it wasn't getting fuel? The motor up and died and this could be a bad connection, and connection could be on the kill switch, ignition key, main power relay, another connection

there is a connector with a cap on it that houses 3 fuses, its near the diag port back by the distributor, pull the cap off, fuel pump is one of these fuses if your referring to the high pressure pump.

I found the fuse for the fuel pump and it was blown. Easy fix and I bought extras. My main concern is why it blew? Possibly a short in the pump?

I used a jumper wire from the power side of the circuit breaker in the control box and put it to the feed (gray) wire that goes to the pump. The pump began to run. I also tested all the terminals in the connector for the relay and had no power coming in.

OK, that is a bit different then previous statement, so you may have blown the fuse. If the fuse did blow then pump probably gets hot and draws more current

If the fuse was blown... only got a few choices. 1-pump draws to many AMPS especially if run for awhile. 2- wires leading to pump are shorting caused by rubbing to block(ground) or to each other causing short.

main power relay issues possible -

is it the original 1996 fuse??? Lets start with the really difficult trouble shooting first...replace the fuse....... does it pop the new fuse or work fine???