prop for a 25 ft 9.9 pontoon

[Merc_115]

best pitch for such pontoon, just bought the boat runs ok for 9.9 which is lake limit, just want more speed

 

[steelespike]

Re: prop for a 25 ft 9.9 pontoon

To do this right we need your present prop size,year of motor and max rpm and speed. You may allready have the right prop. An induction tach like the Tinytach should work and a gps for speed.
Prop size should be near the base of the blades or under the prop nut.
A 9.9 on a 25' toon would very likely use a 5" pitch and a 4 blade would be best.You should have the tach to be sure the motor operates within it rated rpm range.You aren't likely to see much change in speed but the motor will be much happier with the right prop.

 

[Merc_115]

Re: prop for a 25 ft 9.9 pontoon

mine isnt off yet but the marina where boat is docked said they all use a 9 or 10 pitch, not sure if i even need 1 as i use the boat daily, its just mine is pretty battered and looks small, its a 3 blade as everyones is, but when docking i notice all the other pontoons with motors up have alot larger props, given most are 4 strokes but all 9.9, as for the year its 1985 evinrude 2 stroke 9.9, has no rpm guage, seems as if the motor revs alot higher than use to, figured prop was wore