Checking a propeller Shaft?

1NewBoatGuy

Petty Officer 3rd Class
Joined
May 9, 2013
Messages
94
I was out boating a few weeks ago and hit a floating log or something big. Busted a blade off my prop. Well now I am suspecting problems with the shaft as well. I used a dial indicator to check for straightness. How straight is striaght? what is the allowable fluctuation. I these things are not perfect, perfect...
here is a vid of my check
https://drive.google.com/file/d/0B5aDcdq3l9-iRHpsUEZYMmd4UlE/edit?usp=sharing
It may be a little blurry, it shows about .004" of fluctuation.
 

Will Bark

Lieutenant
Joined
Aug 1, 2010
Messages
1,470
Put your new prop on and go to the lake; run the boat at different speeds; if it vibrates or shakes then it is too much.
 

1NewBoatGuy

Petty Officer 3rd Class
Joined
May 9, 2013
Messages
94
If it's only .004" it should be okay. JMO.
That's what I figured.

I checked the prop with the same indicator and got differences of .034" on the prop. I'm returning the prop, I think it's junk.

Heres a vid of the prop check.
 

phillnjack2

Ensign
Joined
Apr 30, 2011
Messages
918
what your seeing is that the bell of the diffuser is a miniscule out of line .WOW call the prop police.
and you paid a whopping $130 for this propeller ? I wonder why you didn't get perfection ? it don't happen with 130 buck prop
I mean its obviously just as perfect as the $500 props from other brands isn't it ? NO
I mean its definitely going to be perfectly balanced isn't it ? NO
now it being a rubber bushing in the prop its never going to be 100%, but to be honest this is very good tolerance for any prop
( myself I would never have a SOLAS prop unless it was given to me and keep as just a emergency, but admit this is very good for run out.)

your never going to get it to be within 0.001 I don't care who makes the prop and who makes your engine.
Prop shafts that are perfect from brand new will have a slight difference on your dial gauge as soon as its been used for half and hour.
the dial gauge is for more critical stuff like a crankshafts for instance, the prop does NOT need to be so perfectly aligned due to the very nature of
how it works.
I don't think you would ever find a completely true propshaft on a used outboard engine and not a chance of perfectly true prop that has a rubber bushing.
to be honest your test has shown a very very good prop shaft and propeller.

my own engines propshaft is nowhere near as good as yours and mine runs great.
take the dial gauge away from the bottom of the engine and keep it for something that calls for it like a crankshaft, never even bother
putting it on a prop shaft on a outboard engine.
jack up your car and try your wheels and tires, your gonna be shocked how far out they are !!!!!!.

one last thing do you really expect great things from SOLAS propeller ? as to be frank they are rubbish compared to oem props and many others.
SOLAS are cheap props made in Taiwan, 99% of the time with a prop you get what you pay for .
a decent new prop starts at around $250 will be stainless steel and really does make a huge difference.
youl be hard push though to get a truer prop than that one in your vid.
at the shop they are going to be talking about you forever if you complain about that being out of true .

have you checked it for balance / balance will be more important that out of true.



just my honest opinion.


phill
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,902
.006 is limit for prop shaft straightness in housing , any more shaft needs to be removed and check on V blocks...
 
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