Bent Shaft or Alignment?

[CarpetBagger]

I just got this boat...i bought it used and got a good deal because there were a few issues.

I noticed during sea trial some slight oscilation to the inboard shaft. Originally I thought it may be an alignment issue, but the more i think about it, its probaly a bent shaft.

About a year ago the rear strut was replaced...It was either bent or broken off, I dont know exactly

How can I tell what the issue is here?

Im planning on pulling the shaft this weekend and taking the whole thing to get looked at, prop an all...

[chrisrack]

If you are pulling the shaft anyway, take it to any machine shop. They can spin it and tell you quite easily if its bent. But be aware that bending any modern SS shaft takes quite a bit of force. Just hitting it on a crab pot bouy isn't going to do it.

[miike]

if you had a bent shaft you would have come aground hard and you would have known it. if you are pulling your shaft anyways (so to speak) lay it down on a flat surface and roll it. you dont need a machine shop to tell you its straight.

running around with poor alignment is a good way to take a good hit in the wallet from a transmission rebuild.

[miike]

bring them both your couplings to get refaced

[chrisrack]

True MIIKE, you can roll the shaft across a concrete floor to get a "decent" idea if the shaft is bent but to measure to a necessary 0.005", you'll need a machine shop.

[Dunk]

Originally Posted by chrisrack

True MIIKE, you can roll the shaft across a concrete floor to get a "decent" idea if the shaft is bent but to measure to a necessary 0.005", you'll need a machine shop.

Yep......and before you pull the shaft(s) have someone who knows what they are looking at eyeball the cutlass bearings. Might as well replace them.. Chances are though if you are feeling or seeing and "oscillation" it more than .005 out..

[CapnDean]

If you can get the boat out of the water....or have a diver go over you can check your shaft for true. Simply break it loose at the coupler, affix a gauge to a stringer or something in the boat that won't move. Have (your diver) or a buddy spin the wheel and see if it warbles on you.

If a warbling she should be, don't run it cause it will jam you up on the tranny side.