So it seems that the problem with my boat is back. The boat will start and run strong for hours but once you park it and it cools off it doesnt run right. It will start and take off but will cut out and die shortly after plaining. But if fires right back up then will do the same thing. Ive replaced the coil. dist. Wires. Plugs. Rebuilt the carb. And has all new fuel lines aswell as pump. Anyone have any ideas  on what the problem could be? Ive taken it to a shop three times and every time they change what they think is wrong the problem is still there.  Any advise is very helpfull. Thanks in advance

Also motor is an indamar 454 with holley 750 vac second

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Sounds like a fuel issue to me.  I don't see a fuel pressure gage on your setup, to verify fuel supply pressure when you try to run it after it sits.

X2- on checking the fuel pressure- Get a gauge and verify.  Normally you will get some lean pops and spuddering with fuel issues.
You are running for long periods at a time, is it at a certain fuel level?  You said new distributor? but the picture does not look like a new one. Points or some sort of module? If you put in a magnet module (pertronics), I see those fail (what you described) like that all the time on a lot of the Vintage race cars I race with. We use them cause no aftermarkets billets for a Alpha or BMW 2002. Those guys always carry a spare and they just don't quit a lot of the time the cars just starts running like shit.  If it is points I did not see a ballast resistor, make sure you can run without one on your particular coil and points. Manufactures will have the instructions sheets online for most all parts so you can check OHM on the coil to make sure.
Also check each electrical connection, (give a small tug) as someone said a .10c connector could be the issue once everything is warm.

good luck, lots of good troubleshooters here reading this thread-

JW