New Boat & Its Prop selection

ILHG

Crew Member
Folks, I am hoping for some advice with prop selection on my new boat. Last weekend was the first time I have had it out since bringing it home. I was out working on the break in. I was finally able to try a little WOT & found that I was not able to achieve the RPM I think I should be. I trimmed the motor which helped, but only gained a couple hundred rpm. Im not looking to turn the boat into a rocket. My thoughts are I should be able to use the available RPM band as it is better on the motor, also keeps person in power band. I deally I would like to keep same speed but increase torque. (Not terribly impressed with the hole shot.)

Also I notice a vibration like a tire out of balance a few times at lower RPM's?

Below are the details

190 Sea Runner ET
F150 Yamaha

Current prop: 19-M 13 3/4 "Yamaha SS Reliance Series"

WOT: ~5100 RPM @ ~41 MPH
At ~3600-3800 RPM I cruise at ~30 MPH

I thought the dealership would have tested it out & taken for a trial prior to me picking it up.? This couldn't have happened as there was only 0.1 hr on the motor when I picked it up. Mind you we did get a sea trial when we did the offshore delivery, however it was so rough we never had the chance the really open it up. Lastly, if you follow the break in procedure you would have to put a few hours on it before you could really test it anyways..?..

If my expectations on the prop performance are not inline, please let me know. This is my first time so I truly do not know.
 
I believe you should get 5800-6000 RPM at WOT.
Ask the dealer if he will loan you a couple props to see which performs the best
 
The guys on www.thehulltruth.com are prop experts. In my opinion you should be propping the boat to hit the top end of the maximum rev range with a light load in the boat at normal engine trim. Then, as the boat gets loaded with full fuel, cooler, crew, etc you'll still be propped right.
 
Oh, and I forgot...you've gotta make sure the motor is mounted at the correct height (adjustable via the mounting holes of the engine bracket on the transom). You want the anti-ventilation plate slightly above the bottom of the hull and it should be visible (ie above the water stream) when running at cruising speed. Often manufacturers/dealers install motors way too deep in the water
 
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