I run a 28'Signature Offshore with 3 2.4 ltr
200 hp mercs...2 weekends ago I blew a motor, so I took off that one, took off another one(just put it away as a spare), and put on 2 new powerheads.These were used motors I had just in case... they were new last year, each has only 30hrs on them, they run mint. Here's the question...all 3 of my motors were perfectly synchronized before...now, the 2 new motors only tach up to 4500rpm at full throttle. I didnt touch any of the control cables or anything... the 3rd motor will still tach up to 5500, no problem. These 2 new motors came to me complete, and I know they used to go up in rpm...can anyone tell me how to adjust the throttles to match? If I run all 3 motors at 4500, the throttle levers are not all lined up and I can only get 55mph out of the boat...I used to get 80 at 5500 rpm. Only peace of mind is I wont blow up another motor at 4500.....