Prop selection for 75hp Force

[Jae]

Hello all... I'm having a hard time figuring out which prop to purchase for the follow:

Motor is a 75 hp Force by Mercury Marine, Serial # OE251544 (5250 max RPM)
Boat is a 24' Pontoon with an average of 4-5 people and 15-20 gal. of gas.

I believe the current prop is a 10 1/2 x 13
When I search for a prop using this info I get a recommendation of 10 7/8 x 11.

I'm wondering if anyone out there can verify if either will work or if I should chose one over the other?

Thanks in advance.

 

[Frank Acampora]

Re: Prop selection for 75hp Force

Either will "work" but the larger diameter lower pitch prop will keep the RPM more in line with recommendations. Additionally, the larger diameter has more blade area which is what you need for pushing a displacement hull like yours.

For a 'toon, the 10 7/8 should be the one that was recommended

 

[Jae]

Re: Prop selection for 75hp Force

Either will "work" but the larger diameter lower pitch prop will keep the RPM more in line with recommendations. Additionally, the larger diameter has more blade area which is what you need for pushing a displacement hull like yours.

For a 'toon, the 10 7/8 should be the one that was recommended

Thanks Frank... I was thinking I wanted to go with the one that would keep the RPM a bit lower... and not risk going over the recommendation. Will be placing my order today.

Thanks again.