Prop PROB

[twofing]

I Am Runing an f150 2005 yamaha...<br />should turn 5500 to 6000 RPM<br />I started out with a 14.25 x 17 prop.... turned 5000 rpm 27 kts<br />tried a 14.25 x 15 prop.... still turns 5100 28 kts...<br />just wanted to know were to go from here to bump the RPM to the recomended 5500...<br /><br />thanks for the help

 

[nanoa]

Re: Prop PROB

I recently went from a 19 to 17 for a better hole shot at the high elevation i usually run on my 2005 yammy I still was only running 5400 wot not trimmed but picked up another 400 rpm to 5900 when fully trimmed

 

[twofing]

Re: Prop PROB

trimmed out she turns 5300.....<br /><br />will this harm the motor.... should i try a smaller diameter?

 

[rodbolt]

Re: Prop PROB

before chasing prop problems to far have a dealer run it up on a dyno or a test wheel to insure its producing the correct power. while its rare to have a top end power problem on a new engine its not unheard of. will be a good time to check the hull tach against an inductive tach at the same time. you really want the motor to be able turn 6k with a medium load. I actually shoot for being able to hit the rev limiter with two people and at least a half tank of fuel. that way when you add the ski's,tubes,coolers and the boat starts getting heavy it wont lug.