65horse johnson

[j-mopar]

hello,I have recently purchased a 1972 seamist with a 65 johnson stinger-2.there is no prop on the motor.can anyone tell me the gear ratio of the motor(1973)? What type of speed to expect? she's a 16' fiberglass v-hull.This is my first boat and I dont know too much about them but am trying to learn.I was told she ran about 30mph with a 13.25x17". to use the prop calc. i need the gear ratio right?

 

[Joe Reeves]

Re: 65horse johnson

J_Mopar.... No, you don't need to know the gear ratio to pick a prop. I could look that up for you (the gear ratio) but the alarms set right now and I can't get at the books.<br /><br />Just go to your local dealership and tell them what type and length boat you have, and of course what engine you have. They'll have a chart there whereas they can pick the proper propeller.

 

[alcan]

Re: 65horse johnson

Hello J-mopar<br /> My book says the prop gear ratio is 12:29. as Joe stated its not nessasary in slecting a prop. That motor was supplied with a 13.25 x 17 three blade, stock.

 

[ob]

Re: 65horse johnson

Mopar, Your motors full throttle operating range is 5500 to 6000 rpms.Select a prop that will allow your motor to run in this upper range at WOT with medium weight load.If your rig is not equipped with a tachometer I highly recommend you have one installed.It will enable you to monitor the engines performance and help you determine final selection in props.Without one you stand the risk of under or overpropping which will result in either lugging or overreving engine.