Back to the main site

Choosing the right Propeller

H

hshanaha

Member
Messages
5
Reaction score
1
Hey everyone, I am sure this topic has been beat to death, however I searched for my particular boat/engine and didn't find anything so I am hoping someone has some insight for me.

I just purchased a used 2011 2550 RCL with a Yamaha f250. It has the ESP package, center fuel, and lifting strakes. GPS shows at 6000 rpm's I am topping out at 35.5 MPH. I would have thought this set up would easily get over 40 mph. Upon further review, the current prop is a Yamaha stainless 19 pitch and 13.75". I would have thought a 15 or 17 pitch and something over 14" would have been a better choice. Any suggestions? I am hoping to at least narrow this down to a couple.

More top end would be nice, but really I would like to run around 3800 rpm's and get more than the 21 mph (GPS) that I am getting now... Maybe 25-27 mph.

Thank you!
 
What's the max RPM's for that engine? Need to know that first but I would agree.....I would think a 17P and a diameter of 14.5 would be pretty close, which is exactly the size prop I just got today. Again, need to know my first question.

Keith
 
I use a 14.75 x 16 Enertia and am around 42 mph @ 6000. Gerry
 
I vote for the 17p Enertia.
 
I just looked at one spec for the 250SHO, they used a 15 1/2 x 17 (on a 2275) and had top speed 47 mph, 4000rpm was 31 mph, 3500rpm was 25.5. Oh and it was a Yamaha Saltwater Series II. Not sure what kind of difference with the f series to SHO
 
hshanaha said:
Keith, the max rpm range is 5000-6000.
Click to expand...
Well then if you're already near/at the max RPM for your motor and still able to turn a 19P prop then you're there.
 
I don't think his prop has enough diameter.
 
Carl is correct, not nearly enough diameter. Fact is, that small diameter prop shouldn't be used on that large gearcase period. The exhaust is traveling both thru and over the prop hub which is causing excessive prop slip. Put the correct prop on that engine and you'll be happy, happy, happy.

I would think that the 15.5 x 17p would be a good choice.
 
Last edited by a moderator:
Well that's what I initially thought as well but he said he's at the max rpm for that motor. Definitely agree on a 17P. The basic principal of a prop is the higher the pitch your motor can turn closest to the max rpms that the engine is rated for, the faster you'll go.
 
Ben and Suzy,

I spoke to a Bennington Dealer today that tries a lot of different props and I think you may be right on. They said the best luck they have had was with a 17p x 15.5" for that particular engine. They also said they have been having very good success with a Solas Rubex L3.

Does anyone know of a place that "rents" props for trial? I would love to try a few different combinations just to make sure.
 
I think Carl has had good luck getting his on Ebay and then reselling what didn't work. I'm excited to see your new numbers once you get it dialed in.
 
Which Yamaha F250 do you have? The 3.3L or the new 4.2L ? There is quite a gear ratio difference between the two which will definitely require a different pitch prop.

The Yamaha Saltwater Series II is a very good prop for your motor.

I'm a big Solas fan. I run them on our Suzuki and Yamaha powered tritoons. It's hard to beat the performance and price. You can find good prices and a great return policy at boats.net.
 
Last edited by a moderator:
That gear ratio difference and the impact on prop size is something I had not considered before. I get what you are saying, it makes perfect sense, I just hadn't thought that far into it. Just one more angle to an already hugely complicated thing, but I learned something. Thanks!
 
You must log in or register to reply here.
Back
Top