Rpm

[mhill316]

I have a 1991 18' SunTracker pontoon with a 1989 28hp johnson, The wot rpm is 4400 at 12 mph,with a 91/4 x 11 prop. Is this rpm correct. One person says this is correct due to load another says it should be around 5400. Can't find rpm specs for this motor.

 

[F_R]

Re: Rpm

Should be 4500-5500 range. So you are just a hair below the minimum. Do you run it at wide open throttle very much? If you are like my pontoon friends, you don't. But if you do, it wouldn't be a bad idea to drop down another inch on the prop. Otherwise, I wouldn't stay up at night worrying about it.

 

[tashasdaddy]

Re: Rpm

your motor developes 30 hp at 5,000rpms, with the poor fuel we have these days the 5400, would be good. right now you are lugging the motor.

F_R and I were posting at same time. as you can see we agree. 9 1/4 x 10.