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Prop pitch???

VernonW

Well-known member
I have worked on this project, just so I would kinda know what's going on.
I read all the blogs, I even talked to my bud Dudley and we have have come
to the QUESTION OF WHY? I started out putting my made in the USA Johnson
magnetic angle locator on the hub, 0 degrees, brought the 2 blade power shift
around and checked the degree of angle at the same place twice. set the angle
at 2.5 degrees and turned on the O540. It managed about 2900 RPM'S.
Checked the angle again and it was still 2.5 degrees. All of this was done on the
right(starboard) side of the boat in the back. Moved the prop and checked it again,
everything still the same. So now here's the question, why is the degree of angle different on the port, if the prop is set at the same point when I check the degree of angle on the right?

PS when I started out on this the angle was 4 degrees different on the R & L.
with some vibration and lower RPM'S.

Hope you can help,
Vernon (wynnboat) Wynn
 
I just knew this was gonna be a problem when I started.
I just wanted to set the prop with the same pitch.
It turned out to be blurb for me and Dudley. We talked
back and forth and still don't know what to think.
All I know is the 0540 turns up to what I want and I don't
have any vibration.

Thanks for the input.
 
Grant , you just don't understand, it did not sink in. But you are right!

I think he is saying he has a reading of 2.5 on the right and a different reading on the left. The leading edge has flipped over from right to left. Props are not mirror images of them self's.

Measure your blades angle in the same position and at the same point on the blade. Record the data from the same side. Now go to the other side and take a reading. If you get the same reading on the same side then you are good to go.

Say right side: blade one = 2.5, Blade 2 equal 2.5

On the left Blade 1 = 4 , and blade 2 =4. Then I think you are good to go. See if the blades tips track the same at a given point or two.

It can't be the same because the leading edge is 6 to 12 inches out of position.

Dawg gone it, maybe I just got con fussed.
:D

Good question, hopefully somebody has the true information.

That was just a SWAG. (Scientific wild a$$ guess)
 
You are right on Diver, I just thought I was trying to get the same on both sides.
And I did, got the same reading for both on the right, and the same for both on the left. Just couldn't figure out why they were not the same.
Thanks
 
2.5 DEGREES IS NOT VERY MUCH. YOU MIGHT WANT TO PUT MORE PITCH IN TO MAKE IT MORE EFFICIENT.
 
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