need a new prop...suggestions

[jelli]

so i got a 73 johnson 25 hp for allmost free but needs new prop it does not have one. its going on a chrystler 1975 tri hull thats been guted to make a fishing boat weight is 800 pounds loaded. i know that its under powered but its what i got i dont care to much about hole shot or speed but with my 20 hp suzuki i can get on plane with me init but if a freind comes along i cant so a 25 should have no problems with just me but i would like to get up with some one ellse in boat. i think i just want a good allround prop never going to ski or pull any tubes but would like to get on plane i dont know rpm and weight is a guess so any suggestions.

 

[usskydvr]

Re: need a new prop...suggestions

Do you know the prop size on the 20 HP Suzuki? That may give a starting point. Aside from that I would say a 9 x 10 p/n 383629
or Michigan 012011.

 

[steelespike]

Re: need a new prop...suggestions

The motor came with a 10" I think with that boat I would go with a 9".
Be sure the motor is mounted as high as possible.Won't be able to be as high as newer gearcases allow but work on the height.Just lay strips of wood on the top of the transom to support the motor till you tighten the clamps.Be sure it is in excellent tune, firing on both cylinders.Throttle plate opening all the way.Bottom clean and smooth.Eliminate as much weight as possible,maybe a 3 gallon plastic tank, a 25 will run about 1 hour at wot(wide open throttle) on 3 gallons.lightweight danforth style anchor. plastic oars instead of wood.