I have a 87 model 28 ft cabin cruiser with a 5.7 Mercruiser in it. The engine runs great for about 45 min to an hour after we hit the water. If I run it hard after that length of time it starts to lose power and acts like it is starving for fuel. If I let it idle for a few seconds it will throttle up to power for a few seconds and lose power again. The temp stays between 140 and 160 all the time we are running so I don't think it is running hot. I have replaced the fuel filter/water separater and taken the screen out of the line into the carb and it was still fairly clean, but I blew it out with an air hose anyway. When it loses power, I have found that I can get into the engine bay and crack loose the fuel filter releasing pressure and it will regain power for a little while, but it will do it again after a few minutes. Is it possibly a vapor lock and if so how do I stop it? Terry
