How bad is this?

mogfisher

Petty Officer 1st Class
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Jul 13, 2009
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237
So I was out fishing and let a buddy drive. He hit a rock. It was at idle speed and a quick bump but it hit the prop and bent it ever so slightly. My question is whether it is necessary to spend the 170 ish bucks to have it straightened or if it's just not bad enough to worry about. Its a stainless prop and it's only bent maybe 3/16" for a length of about 2 inches. It's on an 89 Merc 150xr4 with a non xr4 lower unit. It's the regular size bullet. I've attached pics for reference. Thanks for the input.
 

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Sea Rider

Supreme Mariner
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Sep 20, 2008
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12,345
Gee such a nice SS prop. That prop will be out of correct balance at higher revs, a matter to test. Anyway if with vibration will end having issues with prop shaft, oil seals. One story is boating at idle, fast idle speed, other at power. Let's hope that prop is ok and not with a spun hub ?

Happy Boating
 

mogfisher

Petty Officer 1st Class
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Jul 13, 2009
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237
The prop ran fine the next day. No "noticeable" vibrations and I didn't even notice it was bent until the end of the next day (happened at night, went fishing again in the morning) Has there been any success to someone bending it back and filing it smooth? Like I said, it was very slow speed and is a very slight deflection.
 

gm280

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Jun 26, 2011
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I have to agree with CV16. I am certain you introduced an imbalance into the equation now and even if you can't feel the vibration, you have to know it is there. With that stated, only you can make the determination if the money is worth the effort. Understand though that most boaters are running out of perfect balance props. Any difference between one blade to any other introduces a balance issue. Just the nature of the beast. And that out of balance does work harder on the prop bearings and seals without question. JMHO!
 

Sea Rider

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Sep 20, 2008
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How about at half speed or full throttle, does prop vibrates ? Personally like all my prop blades to be 100% straight as when factory delivered, OTOH, are cheap alum ones which are cheaper to repair at a prop shop.

Happy Boating
 

Chris1956

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Mar 25, 2004
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27,003
It would take a pretty hard bump to bend a SS prop that much. If it were aluminum, I would heat it with a torch and hit it a couple of times with a hammer. Anyone know if that would work with SS?
 

Starcraft5834

Lieutenant Commander
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Jun 2, 2013
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1,677
my thought too Chris.. saw the pic and first impression to bend SS had to be a pretty good whack... I'd only run a SS blade in waters where little to no chance of hitting a rock, would run Aluminum only.... other thing is the prop shaft damage, aluminum will bend in half before the prop shaft is damaged, SS, not so much,, that's hard metal there...

Mog, take off the SS prop and "spin the prop shaft" keep your eye on the milled little hole on the center of the prop shaft....if you can see "wobble" your prop shaft is bent,, if no wobble, your good to go.. put an Alumimun on it for the rocks,, up my way.. when fishing in the St Lawrence River,, rock central!! and shallow in spots... SS runners brave souls
 
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82rude

Rear Admiral
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May 8, 2012
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4,082
A good prop shop can fix that and balance.A good friend of mine has been doing props for years and ss is just more of a pain that's all.Theres a point where its almost impossible to work with it but your not there.from what I see .I run a ss prop right now but I could travel my reservoir blindfolded now.Biggest danger is driftwood which so far the ss has handled with no problems.If I was boating in unfamiliar waters I would switch to aluminum as ss is very unforgiving..
 
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mogfisher

Petty Officer 1st Class
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Jul 13, 2009
Messages
237
Its funny how we ask questions we already know the answer to. lol. I guess maybe I was looking for a "just whack it with a hammer and run it" response but I knew what I was working with. It honestly wasn't a huge hit. Like I said. Idle speed because I knew we weren't in much water. I guess it hit it just right. I think it's going to be a new aluminum prop for me. Cheaper than fixing this one and I just don't care that much. I use this boat maybe 3 times a year. If it were my saltwater boat that I use quite regularly, then I'd probably spend the money but having two boats to maintain, especially when one of them is older, really eats into the toy budget. Thanks for the input fellas. Also, since I swapped lower units (diff ratio) the prop isn't the correct one anyway. It was close enough not to bother with, but not perfect. Guess it's time to get it right now. Thanks again!
 
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