gaiter

I have a 2001 Chaparral with twin 350 Mag MPIs. After running for a full day, we stopped at a sand bar for an hour or so, and when I it was time to go, the starboard engine would not start, just crank and stutter, but would not run. As luck would have it, about half way home, it started so now I have a problem I can't really troubleshoot. What I did find though is when the starboard engine primes the fuel system, the pump sounds eratic, whereas the port side is very smooth. I have repaced the fuel pump, fuel filter, swapped relays and ECMs between the motors. I swapped the feeds at the tank as well between the engines. The new pump still sounds the same. The only thing left is the regulator. Does this even come into play when the engine is priming? Am I barking up the wrong tree if the engine runs fine when it is running? I have not yet checked the fuel pressure, but as I said, it runs fine when it is running. Could it have just been vapour lock? Or would that have affected both engines?
Any ideas would be great

ezstriper

sounds like typical merc vapor lock...not uncommon...

gaiter

What about the erratic sounding pump? Is this typical as well? I probably would not have clued in if it wasn't for the other one sounding so smooth...

gaiter

BTW I am really pissed about the 500 I dropeed on that fuel cooler/pump kit to no avail...win some loose some when u do your own work I guess.