Low RPM

Smoky Mountain

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I have a 2012 2274 with the express package Strakes on the center tube.

The 150 Yamaha came with a 15.25 x15 which the Dealer said was "right" for my boat. With two persons full fuel calm seas no wind I'm only able to reach 5400 rpm wot. Bottom clean new boat. 34 mph on the gps was it.

I tried different trims and that was the max.

The dealer has ignored my commentary.

I'm told that I should be setup for about 5800 to 6000 and then run as necessary.

What do you think? This is always running in the low rpm range at the typical use speed of 20 to 25 mph.
 
Double entry
 
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This was some commentary I received when I posted this on the general section.
 
I don't have you an answer, but I do have a question. Which brand prop are you turning?

Steve
 
I have a 2012 2274 with the express package Strakes on the center tube.

The 150 Yamaha came with a 15.25 x15 which the Dealer said was "right" for my boat. With two persons full fuel calm seas no wind I'm only able to reach 5400 rpm wot. Bottom clean new boat. 34 mph on the gps was it.

I tried different trims and that was the max.

The dealer has ignored my commentary.

I'm told that I should be setup for about 5800 to 6000 and then run as necessary.

What do you think? This is always running in the low rpm range at the typical use speed of 20 to 25 mph.
I think you should try what I have, 15x15p Enertia. We have the same boat and I think the "R" is heavier. I love this prop.
 
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Don't know. It's black. It came on the Yamaha as standard so I'm thinking painted stainless.

http://www.yamaha-motor.com/outboard/powermatched/2011_prop_pdfs_4_18_2011/L150~LZ300%20(V6);%20LF150~LF300%20(V6)%20-%20counter%20rotation.pdf

15.25 by 15 as shown on the chart.
Sounds like "it could be" a Solas aluminum.... the Yamaha 15 pitch will turn about 5 to 600 rpm more, you will have to look at the speed, it could go up slightly, stay the same, or be a little slower.

Steve
 
you will have to look at the speed, it could go up slightly, stay the same, or be a little slower.

Steve
Gee Steve, you really narrowed it down, Hehe :)

Derrick
 
Derrick,

As you know until you try different props you will not have "your" answer. He seems to be worried about RPM, I was too, I changed from a Solas to a Yamaha with exactly the same pitch and picked up almost 600 rpm. I gained about a 1/2 MPH but I think I like the slower turning prop better and give up 1/2 MPH. The engine runs quiter, I don't have to turn as many RPM at "my" cruise speeds which should use less gas.

That is axactly why I said; "I don't have you an answer, but I do have a question." Too many variables when talking about props.

Steve
 
Derrick,

As you know until you try different props you will not have "your" answer. He seems to be worried about RPM, I was too, I changed from a Solas to a Yamaha with exactly the same pitch and picked up almost 600 rpm. I gained about a 1/2 MPH but I think I like the slower turning prop better and give up 1/2 MPH. The engine runs quiter, I don't have to turn as many RPM at "my" cruise speeds which should use less gas.

That is axactly why I said; "I don't have you an answer, but I do have a question." Too many variables when talking about props.

Steve
Hey Steve, notice the Hehe and :) after my comment? It was in fun to the exact part that I quoted, it'll either go up, down, or stay the same, I found it humorous because there are no other possibilities, that's all, wasn't making fun of your post, just that part made me chuckle. Thus the Hehe and :) !

Derrick

Let me also add that I and everyone else on this board APPRECIATE the effort put forth by all members to help out with other members problems and concerns to try and figure stuff out, it's a great thing. I would never 'make fun' of someone trying to help someone else, I mean hey, you know more than I do about it! :)
 
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Derrick,

No harm no foul, it was taken in jest. I thought maybe my first post could have been clarified some. Can you tell I'm a politician? ;)

It might be a tax but then again it really isn't a tax, it's just policed by our Internal Revenue Service :blink:

Steve
 
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The dealer has agreed to work with me to get the RPMs in the zone. I'll report back. I don't know how long this will take. I guess the tech has to come out with a selection of props to swap and try.
 
As I mentioned to you on another posting, my 24' SSLX came with a 14 pitch M series Performance Plus Yamaha prop, and it's pulling 6200 rpm's--too many rpm's. But it's also just a little slow in top end mph, but better than you're seeing. My prop has a M14 cast into the barrel. You probably also have a Yamaha stainless prop in black paint.

But, the standard for this engine is the Reliance 15 pitch prop--a relatively new product offering. "Reliance" is cast into the barrel of the propeller, and it's easily identified by the name. I'm swapping for the Reliance 15 tomorrow.

Ask your dealer to swap your prop for the latest and greatest. It's his responsibility to get you propped/setup properly.

FYI: My motor is in the second mounting hole--mounted about 3/4" above being completely down on the transom. Unless a boat engine is at the right height, experimenting with props is a moot point.
 
As I mentioned to you on another posting, my 24' SSLX came with a 14 pitch M series Performance Plus Yamaha prop, and it's pulling 6200 rpm's--too many rpm's. But it's also just a little slow in top end mph, but better than you're seeing. My prop has a M14 cast into the barrel. You probably also have a Yamaha stainless prop in black paint.

But, the standard for this engine is the Reliance 15 pitch prop--a relatively new product offering. "Reliance" is cast into the barrel of the propeller, and it's easily identified by the name. I'm swapping for the Reliance 15 tomorrow.

Ask your dealer to swap your prop for the latest and greatest. It's his responsibility to get you propped/setup properly.

FYI: My motor is in the second mounting hole--mounted about 3/4" above being completely down on the transom. Unless a boat engine is at the right height, experimenting with props is a moot point.
I keep forgetting to look at what is stamped om the prop.

I'm going to remind the dealer about the height. They have been a Bennington dealer for a number of years hence I would think they have the mounting down but need to confirm.

Min is already a 15.25 x 15. What Is the total spec in the Reliance?
 
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I wouldn't expect much more out of your under deck setup. Strakes on all 3 logs would bring it up more, but the express tube package won't yield the same results as an ESP, and way less than an Elip setup.
 
I wouldn't expect much more out of your under deck setup. Strakes on all 3 logs would bring it up more, but the express tube package won't yield the same results as an ESP, and way less than an Elip setup.
With a little tweaking there may not be a lot more but there is more.

I'm thinking 2 perhaps 3 mph and at least 350 RPM.

Maybe a little more fuel economy that will be almost impossible to determine.

It's not operating at its most efficient or living up to its full potential.
 
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I had a similar situation (held down to 5300 RPM) on a completely different boat and motor. My dealer was of the opinion that running a prop like that would hurt the motor by making it work too hard. I dropped two sizes in pitch and got the RPMs up to 5800, and picked up maybe 1 - 2 mph. I'd think it would be worth the $150 or so for a new prop just to get your motor running in the right power band at WOT. Do look at the stamping on your existing prop so you can compare apples to apples.
 
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