Shaft Question - Noobie still learning

New purchase of the 82 Ski Nautique and still trying to figure things out. Thanks to those who have answered earlier posts. Latest thing Im tackling is vibration/shaft rotation resistance/alignment. Note: This boat has probably been driven with this condition for many years...

Have a vibration that begins at 3000 rpm but goes away at 3300 and higher. I can turn the prop by hand about 180 without any resistance. Then it takes some force to continue around. Unbolted the shaft from the trans and it does the same thing. Inside the boat while turning the shaft by hand I hear rubber squeaking at the point where the shaft goes thru the hull. At the back of the boat when turning the prop by hand I hear the shaft strut bushing squeak a bit.

Not having ever done this before what is causing the resistance? Bent shaft??? Is the shaft 2 pieces? Are there bushing where the shaft goes thru the hull that need replaced? Can a bent prop shaft be straightened or is best to purchase a replacement? If need to purchase can anyone recommend? I know a lot of questions but trying to learn. I appreciate the help!

Thanks for the insight! Does it make sense that I have to slightly lift the prop shaft to get it to meet up with the transmission mount?

Pete has posted some good step-by-step instructions for all of your questions. When you search the site, try an advanced search including his handle. I think it's 8122pbrainard (edit-saw the other spelling in a neighboring state to WI)

To start, you want the shaft centered in the strut and then see where that leaves you up front.

Elberts in Oregon, he makes the A.R.E double taper, are you sure you need a strut?
when you unbolt the shaft it is normal once seperated that the shaft will drop, you need to keep one bolt in and keep it finger tight and it makes it easier if you imagine the prop shaft is in line with the crank centerline to check the alignment, take a look at your strut and your log and the shaft should be dead center in the log and not compressing the strut bearing in any way. if ok then proceed to your coupling half check with the feeler blades. if you do a search for shaft alignment this will explain from there on out the corrections you need to make if any

The log is the fiberglass tunnel where the shaft exits the hull - it is supposed to be centered in it. If it isn't, that is a good sign the strut is bent. Also, look closely at the strut bushings (both front & back, you may have to remove prop) is the shaft is compressing the rubber on one side, the strut is bent.

That silicone says the strut has been off before. I would pull it off and see if there are any shims under it; plus it needs to be remounted anyway. I also think you need a new cutlass bearing; looks like it is breaking down, and it shouldn't be inset on the one end.

It doesn't look far off. Probably no need for a new strut. Saving a little cash is always good if it works out!

The real experts will chime in...though for myself, I'm having a hard time keeping up these days; much less trying to help. I'm sure many are grateful.   LOL   

65,
Your pictures are pretty close up to really get a good look/line of sight from the aft end that may show a bent strut however, just as Greg has mentioned, struts can be shimmed/twisted to aligm the shaft with the shaft log/hull hole.

Before you go and get a new shaft, see if you can get or borrow a dial indicator. Pull the prop, clamp the dials base off to the strut and indicated aft towards the end of the prop taper. This will tell you if the shaft is bent aft of the strut. For a bend forward of the strut, you can use the dial or check it as part of the shaft/engine alignment procedure.

Spent most of Saturday installing new shaft, straightend the twisted strut, installed new bushings and aligned engine. When finished I could spin the prop with 1 finger. Sunday drive produced a totally different boat. Quiet and smooth. Thanks to all the post and help! Any prop recommendations? Would like to get a little more power out of the hole. It has the original Federal 13x13??