Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: prop size for 18 outrage?
Posted by sammidog on 09/24/11 - 6:39 PM
#1
I bought a 1986 18 ft outrage with a blown 150 evinrude engine due to carbon buildup breaking a ring as best I can tell. I bought a used 2006 150 Johnson that runs well. It has a prop 15.5 dia by 14 inch pitch. It will run 5500 rpm. The blown engine has a 14.5 dia by 19 inch pitch. Any idea which would be better or is it a wash.
Posted by msd58 on 09/25/11 - 2:19 AM
#2
sammidog wrote:
I bought a 1986 18 ft outrage with a blown 150 evinrude engine due to carbon buildup breaking a ring as best I can tell. I bought a used 2006 150 Johnson that runs well. It has a prop 15.5 dia by 14 inch pitch. It will run 5500 rpm. The blown engine has a 14.5 dia by 19 inch pitch. Any idea which would be better or is it a wash.
I would guess the 19" -What is you speed with 14" at 5500?
Posted by southwindphoto on 09/25/11 - 4:52 AM
#3
I just purchased a 17 Outrage 1999, with a 1999 Merucry 125 HP and the factory prop alum was 21x 12-3/4...
[southwindphoto -- Please feel free to start a thread to discuss the propping of your boat. It becomes very confusing to combine propping discussions of two different boats with two different motors into one thread. Thanks.]
Edited by Tom W Clark on 09/25/11 - 11:39 AM
Posted by Tom W Clark on 09/25/11 - 11:37 AM
#4
A 1986 Outrage 18 with a 2006 Johnson 150 should be running a 14-1/2" x 19" OMC/BRP SST/SSP/Viper propeller if a factory prop is desired.
There is no way on Earth a 14" pitch prop is right on that boat. At 5500 RPM, the 14" pitch prop cannot be allowing your boat to go faster than 35 MPH and we know that boat/motor combination is good for 45-48 MPH.
*If* 5500 RPM is all that motor can reach with a 14" pitch prop, there is something very wrong with it.
Posted by sammidog on 09/25/11 - 7:14 PM
#5
I must not have been clear. Right now, on a working Johnson 150, the prop is 15.5X14. I don't know the speed as I have never taken my gps out with me yet. I've only had the boat out twice. The prop that was on the boat when I bought it, a not running evinrude 150, is a 14.5X19. So are you saying I should change the props to the smaller 14.5 diameter because the pitch is better suited to the boat? I ran the boat to 5500 and stopped because I thought that was the maximun rpm and did not want to damage anything. And, if they can be trusted, the paddlewheel speedo on a lowrance fishfinder said about 34 mph if I remember right. Oh yea, they are both stainless steel props.
Edited by sammidog on 09/25/11 - 7:29 PM
Posted by Tom W Clark on 09/25/11 - 9:48 PM
#6
Yes, take the 14-1/2" x 19" prop off the dead motor and put it on the new one. It will be a good fit.
Posted by sammidog on 09/26/11 - 4:23 AM
#7
Thanks Tom. I will give it a try.
Posted by dreilly on 09/27/11 - 9:02 AM
#8
Sammi,
I'm running a 15-1/2" x 19" on a 150 Yamaha.
Posted by sammidog on 09/27/11 - 8:34 PM
#9
Thanks, dreilly, i'm definatly going to change it over to the 19 inch pitch.
Posted by sammidog on 10/08/11 - 1:54 PM
#10
OK, I put the 14 1/2 X 19 stainless prop on the boat and ran it today. What a difference! 5200rpm and 46 mph. It was not dead calm and I didn't want to spend too much time with the trim but that seems to be the right combination.
Posted by Tom W Clark on 10/08/11 - 9:28 PM
#11
So, from 34 MPH to 46 MPH. Amazing what a well fit propeller can do for a boat's performance, eh?