NyTrix

Hey All,
Hope everyone had a great Memorial Day weekend.Let me start with what I have. 1994 253 Convincor, 502 Fuel Injected with an M-3 ProCharger which warranted the need for an electric aftermarket fuel pump. I bought the boat last spring and didn't have any electrical issues all season. Here is my issue now. De-winterized it in the driveway and started up fine with the exception of the fuel pump on turning on for the first couple times I turned the key. Finally turned on, engine fired right up and didn't think twice about it. Hauled it 3 hours down to Cumberland, put it in the water and had nothing for power, lower unit wouldn't even go up or down. Pulled it up to the top of the ramp, cleaned the battery terminals (which appered to be clean), noticed my ground between the two batteries seemed loose. Tightened everything, boat came back to life and we hit the water all day. Here's were the mystery starts. On the way back to the marina in the evening we were running and turned the captain's call on an off a couple times. On the third time they wouldn't kick on. Idled down to take a look for any loose wires and didn't see anything. Met my buddies in a cove were they were water skiing and shut my boat off. Sat for a little while till they were finish. Went to start the boat again and fuel pump wouldn't turn on. Engine was cranking fine. Opened the hatch and found a burnt up end of a wire from the fuel pump to a relay. Wiggled it a little turned the key and it started right up AND the captain's calls kicked on. Got it on the trailer, replaced burnt wire and relay and still aren't getting any power to fuel pump.

We can bypass a couple things and get the fuel pump to turn on so we think it is ok. We've checked the ignition switch and it seems to be getting good current in and out of it. My buddy said he was having a hard time finding a good constant 12v current between the ignition switch and relay. Haven't been able to run every wire down yet but so far haven't seen anything loose or burnt.

Any help would be greatly appreciated.

TWIN-SPINS

pull apart and clean the terminals,at the main engine wiring harness,,,it will be a 10 or 14 pin,harness,should have a clamp around it holding it together,,,dont over tighten clamp after

mr3dman

Also, check the starter cable. Sounds like you have multiple loose connections roaming around your engine room. Check the block grounds, everything. Loose connections= High resistance and melted wires

NyTrix

Thanks for the advice guys, I'm gonna be digging into it this weekend with a neighbor mechanic. Hopefully we can bird dog this without too many headaches. Anyone else, feel free to add. I'm all ears.