Maybe another fuel issue, i hope its simple and easy

[bamafutbal]

ok, i read all the posts on the deaconblues thread and want to say i have the same problem. the boat difference is that i have a 2000 searay sundeck with a 5.0 mercruiser EFI. The problem happened once before in september on our last outing of the year. We were at st augustine, after multiple stops throughout the day including capps for lunch we pulled up to a sandbar at the end of the day and did some exploring with the kids for an hour or so. Boat cranked up, i put it in reverse and it choked out, cranked again with bogging, and then nothing, 10 minutes later, crank then bog out, waited 10 more, then 15-20 more, then called a buddy. well 30 minutes later as he arrives, it starts and no more problems. Replaced water fuel separator when i got home and no water in the filter. Today i ran the boat for the first time this year after getting thermostat, plugs and all fluids changed last month. I noticed that temp stayed at 180-190 all day long with outside temp mid 90's, manifolds were not too hot, could keep my hand on them two or three seconds without a quick recoil of pain, so that was good because that is the way it has run for last 50 hours i have owned the boat. the boat was stopped and started 10-15 times for skiing and wakeboarding. Kids had enough so out to the middle of the lake for a snack while i blow up the inner tube, 30 minutes later, i am pulling both of them up and after 100-200 feet, its bogging and the cuts off, restart it and it revs up and dies, repeats for next 2-3 times then give it 10 minute rest...boggs then dies...10 minutes later it will not even fire for next 5-6 times over 45-60 minute timeframe. finally someone offers a pull and 3 minutes into our pull i decide to try and crank it, wow perfect start up, so i let it idle 3-4 minutes while he is still pulling us and then i motion him to stop, everything sounds and looks perfect so i thank him and pull the kids tubing for next 30-45 minutes turning boat on and off, but only for minute or two at a time. Get home, place the muffs on and starts perfect again, WHAT GIVES?