Correct prop for 228 Seafarer with F225 Yamaha?

[c1steve]

My 1996 boat has the 15.5x17 Saltwater Series II prop, and it seems to be too much. Hole shot is good, midrange is okay, but above 22 knots it struggles somewhat. Max speed is 26 knots and 5,100 rpm.

The original prop on a 258 with the same engine is 13.75x19. What do people recommend?

 

[Mustang65fbk]

Yikes... yeah a max speed of 26 knots and only 5,100 rpm is much too slow. I'm not positive as to what I have on mine, just know that it's a 3 blade stainless steel prop. Here's a copy of the performance bulletin from Grady White on a 228 Seafarer with a Yamaha F225 on it. Looks like a 13 3/4" by 17M prop, I imagine it's likely a 3 blade. Good luck!

 

[c1steve]

Thanks for the quick reply. That is a much smaller prop than the 15.5" diameter currently on the engine. Engine is definitely overloaded.

 

[DennisG01]

Steve, something sounds amiss - like maybe something else is going on. Also, I believe you're thinking of prop pitch backwards. Overloaded means the prop is too big - as in too much pitch. If you go up in pitch, you will lose RPM, not gain.

Are you trimming up as high as feasible when going full WOT?

Is the prop in perfect condition?

Is hull bottom perfectly clean?

Responding only based on what you wrote, it sounds like you're not trimming properly

 

[Fishtales]

Two ideas. See if there is a local prop shop where you can test a few different ones out, then buy the one that performs best. 2nd is to check the GW website and see if there are any performance bulletins on the model. If so, they will highlight what was likely shipped from the factory.

 

[c1steve]

Steve, something sounds amiss - like maybe something else is going on. Also, I believe you're thinking of prop pitch backwards. Overloaded means the prop is too big - as in too much pitch. If you go up in pitch, you will lose RPM, not gain.

Are you trimming up as high as feasible when going full WOT?

Is the prop in perfect condition?

Is hull bottom perfectly clean?

Responding only based on what you wrote, it sounds like you're not trimming properly

I am new to running a GW, so do not know the best settings for trim. Yesterday had the Bennett trim tabs down 3-4 LED lights on the display, and set the motor trim to where the boat seemed to run relatively level. Where I am, NorCal, there is always a swell running so it is best to keep the bow down somewhat to reduce pounding.

What do you recommend for trimming the tabs and the engine?

Prop is in excellent condition, hull bottom is clean.

 

[SkunkBoat]

Steve, something sounds amiss - like maybe something else is going on. Also, I believe you're thinking of prop pitch backwards. Overloaded means the prop is too big - as in too much pitch. If you go up in pitch, you will lose RPM, not gain.

Are you trimming up as high as feasible when going full WOT?

Is the prop in perfect condition?

Is hull bottom perfectly clean?

Responding only based on what you wrote, it sounds like you're not trimming properly

the smaller diameter 13.75 vs 15.5 comes into play also Dennis. You can go down in diameter and up in pitch... or vice versa.... or just do one....