Have a 1996 BAJA 252 with the 454 in it, this year it has started to give me some problems. The issue is that after I run it for any amount of time 10 min 45 min, during the run time it works great, but after I shut if off for any length of time, it gives me problems when I start to go again. It will start up fine but as soon as I start to go it will run for about 20 seconds then it seems to lose power and eventually quits. After that it will not start again unless I use starter fluid a couple of times. I thought it was a fuel water issues so I replaced the separator, but that didn't change anything. Not sure what to do next

I'm pretty sure those year 454 fuel systems would vapor lock after being ran.
There may have been a update for the fuel system to prevent this.

1996 454 engine should have a VST. Do a search here on VST.... Lots of information on how they suck.

Is it EFI or carbed?

Welcome to the forum !

x 2 on EFI or carbed ?

I have my bet placed on that he has 454/7.4 LX or 454 mag mpi. Eiter way Vapor lock in the VST.

Leachman, Type this into google. "vapor lock 454 offshoreonly.com". The threads will lead you to the light.

Quick things to try for lets say you need to go boating and have limited time to fix the issue, try adding Mystery Oil to your gas. It will raise you boiling point of the fuel. Run with your blower on all the time. After a run let the engine idle, or about 1000 rpm, with the hatch open to escape the heat and get cooler water threw the engine for 3-5 mins.

Welcome to OSO