So last year I took our pontoon to a reputable shop and had the carbs rebuilt. They told me when I picked the boat up that they could not set the timing correctly on the motor. If I remember right, they said that TDC as 15 degrees and they could only get it to like 5 - 8 degrees. The motor starts and idles fine, but when you go more than say 1/4 throttle, it bogs down and will not open up like it should. Sometimes it might speed up and have a pretty good miss to it. Can anybody help point me in the right direction?