Reply With QuotePut a straight edge on the pad of boat then measure from that to center of prop shaft. Not for sure on yours but should be around 3 inches below pad. If you lost speed then your to high. Your about 300 rpm's to high. Should be around 5700 max.
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Trophy King
Jack Plate
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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Put a straight edge on the pad of boat then measure from that to center of prop shaft. Not for sure on yours but should be around 3 inches below pad. If you lost speed then your to high. Your about 300 rpm's to high. Should be around 5700 max.
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Trophy King
Yea i hit one too many 0's. I have a roller in the way so find something that is long and thin enough is the problem. I agree with being too high. The ramps around here are too busy to just leave your trailer in and adj ect. Which i am not trying for speed just want everything like it supposed to be. Everything works better when it is correct Thanks for the input Cub48
Crappie Wall Hanger II
Every boat/engine package is different.......Raise the engine until the top of the water intake is just lower than the bottom of the boat, your rpm's go up cause you have less drag in the water, since your speed went down your prop slip has increased the prop is up in dirty water.......try a prop with more rake and you will probably need to go up atleast one pitch also....
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Trophy King
Just got out of the shop checking everything measured two different ways and it was on three inches below the bottom of the boat. So i dropped it 1 inch which put it at 4" though i would try it then adjust it up a 1/2" May check around and see if i can find a 25 pitch to try. Thanks everyone Cub48
