Bought new on 17 foot Grumman runabout, always had a minor power loss problem, usually cut out once per trip but ran good 99 % of time. Usually pumping of fuel bulb would solve. This has been getting much worse for past few weeks. Recently towed a 16 foot disabled boat, since then motor will not power up. New spark plugs burn black after short run at max speed possible.<br />Will start fine and run at low speed ok. All new up to and including fuel pump.<br />Need a suggestion on checking fuel system further( going into carbs ) or possible overheating sensors as next step.
