1997 2900 Open, 454 Crusaders. Engines bog after 45min - 1 hour trip

[Roweje]

I have a 1997 2900 open we just bought middle of last season in lake erie (July 2024).  Everything runs great, but struggling with a issue after the boat has been running for 45min +.   If we bring it off plane to idle after 45 min or so, one or both engines will bog down trying to get back on plane.  We have done the following:

1. Ran boat till almost out of gas.  Calculated less that 15 gallons when we filled up 185 Gallons on 200 gallon tank.
2. Ran boat again and ran into this issue
3. Replaced all fuel filters and all water separators after running over 180 gallons back out and refilling gas.
4. Full tune up, including replacing distributor caps, wires.
5. Have noticed, but not did 2 things at once, so I know I need to isolate more:
   a.  A breaker under the steps seems to trip
   b.  loosening the gas cap seems to bring it back.

Unfortunately my season ended before I could get another 45min + ride in so not sure which it is.  Being a 97, would replacing the fuel lines just be a good maintenance project.  What would cause a breaker to trip (fuel pump?).   Just looking for any suggestions that may help trace this down.  Boat runs amazing until it doesn't. The gas cap leads me to believe the gas lines are collapsing.

It is Fuel injected.

I would try to take the gas cap off and try to run it. I had a Chris Craft and my fuel vents were clogged as someone else previously mentioned. I took off the gas caps and ran the boat fine. Made it all the way to the Bahamas and then replaced the screen in the fuel tank vents. Good Luck.