Prop Question for 228G

[bmoore47]

I have a 98 228G with a 225 yamaha ox66. the prop on it is a 13 3/4 x 17. I can turn the prop up to 5700. My problem is at 38 to 4000 RPMs the boat wants to squat and my cruise speed is about 15 to 17 knots. At 4200 to 4300 my cruise speed is 20-22 knots. My mechanic say my best fuel econ is in that 38-4000 range. I feel like I need to change props. Does any one have any suggestions?

 

[NIGHTIDES]

I ran a Stiletto Stainless Steel 14.25x17 on a 228 and at 3500rpm=23mph and at 4000rpm=31mph..

And those numbers are w/ a 200hp not a 225hp like yours. Is your prop aluminum..?? how clean is your bottom..?? And what hole is the engine mounted on the bracket..??

 

[bmoore47]

The motor is mounted in the top hole of both the motor and the bracket. The bottom is clean and it is a yahama SS prop. Thanks

 

[plymouthgrady]

Michigan Ballistic SS. Get the #'s this weekend.
Is the engine down all the way and are you using your tabs?

 

[NIGHTIDES]

The motor is mounted in the top hole of both the motor and the bracket. The bottom is clean and it is a yahama SS prop. Thanks

From what I found, the top hole is the place to be. You can get the Stiletto Stainless prop for less than $300 and it should dial you right in.

 

[bmoore47]

I just talked to a prop shop, he said that the wheel is to small and recommended that i try a 14.25 by 17. Because i need more power and the increase in dia will make a difference. My question is, is that 1/2 inch going to make that much difference? Does any one have any ideas? Thanks

 

[Parthery]

15.25 x17 Merc Mirage Plus (or Thunderbolt which is the same prop without the plugs).

Should give the same rpm at WOT, and your cruise should be a little higher. You will also notice an increase in maneuverability around the dock and at slow speeds, due to the increased blade size.

 

[plymouthgrady]

you can go up or down 1/4-1/2" w/o much of an issue. Once you get 3/4", your performance will change. Remember, up in pitch, down in RPM's.

 

[bmoore47]

I beleive the 17 inch pitch is correct I thinking about going to a 14 1/2 to a 15 inch Dia. Do you have a recommendation on which? The Whole shot and lower RPMS the boat wants to sit down on the stern, once you get get over 4200 rpms the boat planes out fine, but if it slides below 4200 it just wants to sit back down. Thanks Brian

 

[plymouthgrady]

If you're teetering on plane @ 4200 RPM's something is WAY off. You should be cruising at 4200, 30-33 mph, dep. on load. Tabs down engine down @ hole shot? Get boat up on plane and then adjust running angle (w/ trim & tabs). 19 is too much for 228.

 

[bmoore47]

Went to a 15.25x17, what a difference. Thank you everyone for your input.

 

[plymouthgrady]

What are your numbers now?

 

[bmoore47]

My numbers are great WOT is 54 to 5500 speed is 38.7 knots, at 3800 I am running 24.5 knots. i am very pleased and It jumps out of the hole.

 

[plymouthgrady]

nice...but that boat should be pushing 40 easily all day long.