2005 Yamaha F150

[chrissy t]

I have a 2005 Yamaha F150 that I can't get maximum rpm out of. Top end it only turns 5200 trimmed out. On computer printout it showed it turned 6200 at times.I have replaced all filters including vst,had the fuel injectors cleaned and still only 5200. Does anyone known of something I am missing? ps I checked the full throttle position on the cable and it is getting full throttle. Thanks for any ideas, Rob

[almetelo]

That happened suddently or always have been your max RPM?
Are you sure you have the right prop for your hull/usually load etc etc

[chrissy t]

Since I have had the boat,it has always turned just 5200. When I bought the rig I was given a computer printout of the history of the motor. It only had 100 hours on it and had reached 6000 at times.The boat had not been used much since it had 100 hours in 5 years. I drained the gas in the tank and ran it. It runs fine,but does not reach full rpms. That is why I replaced all the filters and injectors.The next step is to check and make sure the tach is working correctly. Thanks,Rob

[99yam40]

might take it to a Yamaha shop and have them check tach and check the motor out by installing the test prop on the motor and running it in tank to see if it can get up to the proper RPM

[BaileysBoat]

If we knew the prop and boat we could help you more.

Are you trimmed out? Is the boat heavy?

I use a 17P on my 19" Stanley and get close to 6000 RPM

[TownsendsFJR1300]

If you've never seen it run over 5200 RPM, there's a possibility someone trimmed the motor high to get that # on paper / in the computer (yep, I'm suspicious).

Go to this site and put in your appropriate information, it'll give you an idea of what prop is required. It may be as simple as a prop change, especially if the motor runs good and the same as it always has in your ownership..

Performance Bulletins | Yamaha Outboards

[Bilge Rat]

A lot more goes into getting the right RPMs out of a well tuned motor than a prop with 17p or 19p or whatever.

Hull type, prop design, dia., motor height, and how you want the boat to handle all play a part in getting the most out of your rig.

Tell us the make, model, pitch of your prop.

Run the boat at WOT recording RPM and MPH. Trim it up a little noting RPM, did the MPH also go up. Find the max. RPM with the max speed. You are looking for the best speed with the least prop slip.

That RPM is your baseline. From there you can start changing things to get the best performance.

Look at the motor height. changing it can help.

You may need a different prop but check the other parts of your setup first.
Different prop designs can help overall.

Research boat setups to help find the best for you. It is not as simple as pitch and rpm.
I run a 17p Turbo or a 19p Power tech. Both are turning 5900 rpm. One is 3mph faster on smooth water and the other is better handling overall and much better in chop.

You do need the RPM up around 6K. Check out all the variables that will help get you there.

[chrissy t]

This motor is on a 218 sailfish. I am running a Solas 14 1/2 by 15 four blade prop. I do pick up 200 extra rpms by trimming out, but still only get 5200. When I get a calm day I want to try another tach.Thanks for all the help.I don't need the extra rpms, but like to know the motor is at peak performance.

[almetelo]

Yes, you'll need "extra" rpm's...
Your motor must be over proped... at WOT must run close to 6000 rpm's

Just to prevent serious problems in the future.

[TownsendsFJR1300]

Just a note. Plugging all your info into that Yamaha performance site, your boat calls for a 200HP (four stroke).

I know you have a F150 and have to adjust accordingly for that.