Yamaha Prop for 21ssx pontoon

[Jim Zagaros]

I need to replace my Yamaha 70 HP prop. The prop that was on the boat was Black in color and I know Yamaha original Proos are White. Leading me to believe it's the wrong prop based on performance and RPM max or 5600.My question is what pitch will be proportioned to my pontoon.
Thank you
Jim

 

[Jack M]

Do you know the size of your current prop?
I have a a suggested prop chart that Bennington provides to its dealers, your suggested size is 13.8 X 13
Also you can contact Ken at propgods.com, he has helped many members here get dialed in .

 

[SOPOPONTOON]

my dealer just suggested and put a 14 x 11 prop on my 70 hp Yamaha on a 20 foot pontoon. gets up to 20 mph at 6200 rpm WOT with 2 adults on board. thinking about dropping to pitch 12 to lower rpms at WOT...any thoughts???