I am wanting to know the correct way to adjust the jack plate on my 285 Stratos with 150 Yamaha. I did the measure with the boat level it was 14 1/2" from the floor to the bottom of the boat it was 8 1/2" to center of shaft. Which is 6" so i raised the engine up 2 1/2" on the jack Plate to raise it the full 3" it would be all the way to the top. I also checked the measure up to the cavitation plate which was 21 1/2" which is 7" One place i read u need 4 1/2" to 5" to cav plate. So i test drove the boat today take off was good planed out quick water pressure was good. But speed dropped 2 to 3 MPH rpm was up 2000 rpm before i was 5800 rpm 56 mph. Today i was 6000 at 54 mph. That was trim up to the max trimmed down a little dropped rpm but speed was not any better. I know the spill adj 1/2" at a time but i need a base setting to start with!! Raise motor more speed or lower motor more speed? by the way the prop did not blow out but i think with the 6000 rpm i was losing prop spin. I think i may need a 25 pitch prop to replace the 23 i have. cub48 PS could not watch cav Plate while running as i was by my self!!
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