Vibration - Prop vs. shaft Round 1

[76NautiquePete]

I bent the prop on my 76 Nautique. Between channel locks and a few light taps of a hammer I was able to get the prop close to its original shape (for the most part) and got back underway. But going past "In gear speed" I get a strong vibration. Could it be just the prop (that I'm sure is still a bit out of whack) or does this sound like more of a shaft issue?

I have a second prop which I'll probably switch out and retry.... Just wanted some input as to wether a slightly bent prop will throw things off that much?


Thanks!

[TRBenj]

RE: Vibration - Prop vs. shaft Round 1

Could just be the prop. Even if damage isnt visible it can still cause some serious vibration.

How fast were you going when you did the damage?

[darrel409]

RE: Vibration - Prop vs. shaft Round 1

Does the shaft spin freely turning the prop by hand? If not, its probably bent or out of alignment. Yes, the prop can throw it off that much. Either one is no bueno.

[76NautiquePete]

Was pushing boat back at dock and prop hit a concrete foundation below water. Not turning... it just bent one prop blade back.... seemed fairly insignificant at the time. Shaft spins no problem and no noticable wobble when put in gear on trailer. I was just surprised that it would vibrate that much from just the prop. But I guess if its getting inconsistent thrust from each blade that will cause a bit of a problem. I'll switch out props and give it a go.

Thank for the input.

[AuMDLST]

fairly difficult to bend the shaft - props bend rather easily to protect drive line including shaft - I have dinged two props so far with an 06 210 - first was very noticable and could not give the boat any throttle without vibration - second ding was bairly noticable and felt the vibration at around 32 mph - does not take alot to send vibrations through the boat

[richard]

if u feel strong impact when hit,and bend the prop leaf deep,u may have a bend shaft,put the boat on trailer,start engine and engage idle,have a visual check on the prop and shaft.if u don't see the shaft turning off axle some where,borrow a good prop for test to water.I need chang my shaft every time I hit stone,that made mor vibration than a reconditioned prop.

[johnjmurray]

My vote is your prop. Even the slightest hit (sandy bottom) can unbalance or bend a prop. Best bet is buy a "new" prop. You can get a good rebuilt or a good new one from www.deltaprop.com, they have good prices. Once you get a new prop on your boat I bet you will notice a HUGE difference. And it's the cheaper way to find out if you need a new prop or if you have shaft issues.