I have had on ongoing issue with my 2003 Mercury Optimax, its a 115 dfi model and I can not figure out the issue. The motor starts and idles fine, I can idle in neutral for long periods of time with no issue, the problem is when I idle in gear for more than a few minutes, or when I take off on a plane a few minutes later the motor sputters and will gradually die out unless I pull it back down to idle speed. However, if i pump the fuel bulb every 30 seconds or so the motor runs perfectly with no issues. Even at full throttle for long periods of time it will run great if someone is back there pumping the bulb. So far I have replace all the fuel lines, primer bulb, low pressure boost pump, built in ff/water separator, and tried a portable tank to rule out the boat side of the fuel system. I have also checked the fuel pressure both at the rail and at the vapor canister and both seem to be in spec. Any ideas or suggestions would be greatly appreciated. Thanks
