Mercury 150 Prop tightness

Remediation

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On the new boat, I was waxing the engine and sprayed the SS prop. When I grabbed the prop to polish it, there is about 1/4" play of back and forth on the shaft.  I was just going to tighten it but thought "ask the forum if there is supposed to be some play or should I just crank down on the nut with a SS prop"  Anybody know the Mercury answer?

Found one problem with the seat on the front of the helm on the fishing model.  Had a friend sitting on it yesterday while  cruising and never saw a buoy floating in the water.  Straddled it between the toons and the prop cut it up.  Never saw it and only knew we had a problem when the motor hit it.  Put some marks and a small nick in the prop.  I will pull it and drop off to check the balance.  First marks on the boat. 
 
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Bruce, load it up with marine grease (shaft and hub) and tighten it up. What was the buoy made of?
 
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I read someplace but have no idea if true.... DO NOT wax your prop.... It kinda makes sense to me......why would you want something slippery trying to grab the water. 
 
Mostly plastic and foam.  On the way back, I stopped at the buoy to check it out and figure out why it was there.  It was a danger buoy because the water went from 75' to 14' at the buoy in the middle of the channel.  It was the first time I have been in the south pool of the lake for 15 years and didn't know it was there.  The prop cut several deep slices into the buoy.  Luckily I didn't catch the rope or chain of the buoy.    
 
I read someplace but have no idea if true.... DO NOT wax your prop.... It kinda makes sense to me......why would you want something slippery trying to grab the water. 
You are properly right but it sure looked good. There is something I read were you don't want a perfectly smooth hull on a runabout.  Small imperfections allow air bubbles to reduce drag on the hull. 
 
yup... there is a lot we don't know, we don't know, ...ala Donald Rumsfeld -----     "There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know."
 
I have always waxed my stainless steel prop......8 yrs!!! No problem!
 
It looks like I ran mine into some sand, just the tip of the blades has some micro scuffs. Should I wax them? I can feel a slight change in texture from the rest of the prop.
 
Oh sure...now you're playing "just the tip" with the folks here too? 

If it were me I'd leave it be. I will have to say I never thought of wax hamper prop performance, I though it was more about clean water which I figured the smother the prop the less "air" it would create.
 
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Oh sure...now your playing "just the tip" with the folks here too? 
Did you want a photo or something? Remember the water is cold here!!
 
And on my yamaha there is no slop in the prop.
 
I found a Mercury video.  The prop should be torqued to 55lbs.   
 
Update.  Sunday morning I got the torque wrench on the nut and it was torqued to just under 55lbs.  I tighten it to the correct lbs and the play is still in the prop.  Removed the prop to inspect it.  It is an Enertia SS  with the 2 piece hub kit. After reassembly, the prop still has back and forth movement.  I think the hub piece with the splines is bottoming out on the shaft before it presses the non splined piece against the thrust washer.  Time to call the dealer and talk to a mechanic.  
 
Update to the update:  Talked to the mechanic.  They changed the bushing design recently.  The mechanics at the dealership noticed the play on new props and called about it.  It is the way they are designed and the play is OK.  
 
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