the motor runs well for about 15 min at 5,000 rpm and then looses rpm to no more that 4,000 and surges, checked bulb while running and it was soft to touch. replaced fuel pump and plugs last year, replaced carburators two weeks ago, and check all fuel lines for leaks, replaced bulb--just empted fuel tank of all fuel but have not had an opportunity to run it yet--can you think of anything else that could be the problem.---also lost all power to console from battery--replaced fuses and check connections--don't have equipment to check power--anything simple I can do with limited resources