need prop help asap!

[craveman85]

Boat is a 1961 alumacraft queen Merrie 18'. Kinda like a very rounded bottom semi v. All together I'llprobably have 1600lbs with the weight of the boat motor gas and people. Its rated for a max capacity of 1728lbs people motor and gear. Motor is a 1976 jJohnson stinger 75hp triple. I have no prop and need a good starting point. I've never dealt with big boats before so no idea on prop selection.

 

[SkiDad]

without knowing your rpm, i would say try a 17 pitch prop.

 

[jestor68]

Wot rpm range is 5000-6000 rpm; HP rated at 5500 rpm.

As a comparison, my little 16 ft Crestliner/70 Johnson just turns 5400 rpm with a 17 pitch. I've ordered a 15 pitch for it to get the rpm above 5500.

Your boat is bigger and heavier, so it can't use a 17 pitch and get to the proper min of 5500 rpm.

You are looking at a 15 pitch or less.

If you can get a prop dealer to let you try out a 15 and a 13 pitch; that would be great.