Change Prop Or Stay The Same?

[POPS PLAYPEN]

I Have A 1992 Searay 270 Cabin,7.4 330hp Eng. It Is Equipped With Trim Tabs. The Current Prop Is The Original 3 Blade Aluminum, Abit Corroded And Very Thin On The Ends. Thinking Of Going To A 4 Blade Ss. The Problem Is The Boat Falls Off Plane At 2900 Rpms. Is This Normal For This Size Boat? Should I Change The Pitch To Acomplish Lower Rpms And Stay On Plane? Thanks

 

[Salmonseeker]

Re: Change Prop Or Stay The Same?

What is your current RPM at Full throttle and what is your current prop pitch?

 

[POPS PLAYPEN]

Re: Change Prop Or Stay The Same?

Numbers Are Not On The Prop I Now Have And The Best I Can Remember From Last Year Wot Was Around 3900 Rpms

 

[steelespike]

Re: Change Prop Or Stay The Same?

If the motor is in good tune it appears you need a prop change.Without your
present prop size,max rpm and speed.no way to know what you need.
GPS measured speed is best.
Take her out for a couple of runs.check carefully for numbers on prop perhaps under the nut.A prop shop can measure it for you.

 

[POPS PLAYPEN]

Re: Change Prop Or Stay The Same?

found out today the prop is a 17". still can't find any numbers for pitch. max rpms according to owners manual 4600-5000.

 

[steelespike]

Re: Change Prop Or Stay The Same?

Still can't make any estimate without pitch.Planing rpm seems in the neighborhood.Have you tried trimming in to keep it on plane?Trim tabs
would help maintain planing speed.Get the prop checked/repaired/sized and test again