Ok, I will do my best to cover all questions asked on this one:

Carbs have been rebuilt and I switched them from side to side, problem stays on the port motor even with switch over.

I know the ingnition is thunderbolt, not sure if it is 4 or 5 though, will check.

There is no rubber fuel line on this motor.

The motor starts to cut out at 4000rpm, when I say "cut out" it is not dying, just starts to lose power and if you don't back the throttle down soon enough it will eventually fall on its face and shutdown. If you catch the cutting out early enough you can back it down give it a few pumps and maintain as long as you do not stuff it back to WOT.

Fuel filters have been changed.

Anti-siphon valve, should be working if boat spits fuel when filling up tank, which it does currently.

I will be up there on Tuesday and will swap coils from side to side and replace the one bad ignition wire. I will also inspect the wire, points, cap and rotor. I may even take a few pics if something looks wrong.

THANKS TO EVERYONE for all your help and suggestions. I will report back with my findings soon.

That's an issue of your fuel tank vent or fill tube. Usually caused by bends and or horizontal sections on either.

Typically caused by fill tube not vertical enough in spots, thus flowing fuel slower than gasline dispenser.

If you vent is restricted, this will cause fuel flow issues to your motor(s).

Splash back has nothing to do with anitsiphon valve in the fuel line fron tank to motor(s).

Saw on your other post that you got the fuel pump installed correctly, did that solve the wot issue?

Negitive. It runs the same as it did before with the old fuel pump.

Water seperator filter. More then likely water...

I think you have a fuel delivery problem from the tank to the pump. Seems like it is running outta fuel on the top end. Put a 5 gallon can in the bilge (bungie it in nice) with a makeshift fuel line going directly to the pump....then run the boat. I bet it will run fine with that setup. You probably have a problem with the pickup in the tank sir.

+1

Agree separate your problems - motor side or fuel tank issue side. Use a 5 gallon remote gas tank with a 3/8 new fuel line . The ones that small outboard motors use and do not forget to vent that remote tank to full open position.

We also like using inline a primer bulb 3/8 - the same as outboard engines use to see sometimes by squeezing it if there is a fuel pressure issue but that only works with 2 people in the boat and if there is not too much fuel restriction. I would also hook a fuel pressure gauge up to see what your pressures are. Good luck.

swap fuel lines from each engine and see if the problem follows the fuel line.

I will try the remote fuel cell and see what happens.

I replaced all the fuel lines from the filter to the engine for good measure, and I saw one had a small kink in it.

Will post results.