Need shaft alignment near Titusville FL.

[Thebaysailor]

Nalani, is a 1980 Bristol 45.5 Ketch with Yanmar power.
I'm the owner for three years and have shaft vibration that limits my revs to about 2000.
I'm looking for a competent yard near Titusville or Ft. Pierce to rebed engine mounts, align shaft and replace cutlass bearing.
Hoping for real life experiences and recommendations from the fleet.
Cheers.

[Cheechako]

I have not experienced alignment so bad it would limit the rpm like that. I wonder if you have a bent prop or something?
At any rate, it's been too long since I was in the yard in that area to be of any help. There was a boat mechanic under the name of Tim's Marine there years ago. If he's still around, he's a good guy and may have a suggestion. The Yanmar parts guy in the little house just North of N. Beach Causeway on Old Dixie Hiway knows him.

[Thebaysailor]

There had been done poor work done, new shaft, new mid shaft bedded bearing, the year before I purchased her.
I found that the engine mounts were loose on the wood stringers and would not tighten as the wood holes were tired, 38 year old boat.
Prop is Max Prop and gets serviced before each launch.

[Hoohaa]

Is she a center cockpit?
I had a very similar problem and spent 4 years looking for the answer.
My boat is a 40f centre cockpit. With a long prop shaft. Long, expensive story but the solution was to get rid of my old stern gland which had some sort of loose cutlass bearing in it. This was the source of a nocking noise and also made it near impossible to centre the Shaft in the stern tube. Which made it very difficult to get an accurate alignment.
Next. Get a rubber cutlass bearing and glue it onto the forward end of the stern tube. Install new dripless seal. Align.. and your good to go.
Regarding alignment. Do it yourself. Had professional's align mine 3 times. None of them got the prop centered in the stern tube or twigged to the real sorce of the problem. Waist of time and money. It's not hard it's just a question of you putting as much time as you need into it.
I will post a link my massive thread on this. Skip to the end for what fixed it.

[Hoohaa]

https://www.cruisersforum.com/forums...d.php?t=174478


Vibrating shaft at slightly high revs.

[Thebaysailor]

Thanks Hoohaa,

She is a CC and yes, longish shaft. I suspected the mid bearing was a contributing factor as it was added and not part of the original design.
I'll check your link and quiz you more if needed.

[sanibel sailor]

also check prop size. If not enough tip clearance, it can cause vibration. I think 15% is minimum recomended. Someone might have thought bigger is better.

[Andreas W]

Good advice. I had a 43 ft CC boat with a 54 hp Yanmar.
I used a stern tube with 2 cutlass bearings made of Vesconite on both sides, and a dripless PSS seal.
Vesconite is better than rubber because it has a lower friction, and it does not swell up. Just make sure to machine 2 spiral grooves per bearing to ensure sufficient water flow.

Originally Posted by Hoohaa

Is she a center cockpit?
I had a very similar problem and spent 4 years looking for the answer.
My boat is a 40f centre cockpit. With a long prop shaft. Long, expensive story but the solution was to get rid of my old stern gland which had some sort of loose cutlass bearing in it. This was the source of a nocking noise and also made it near impossible to centre the Shaft in the stern tube. Which made it very difficult to get an accurate alignment.
Next. Get a rubber cutlass bearing and glue it onto the forward end of the stern tube. Install new dripless seal. Align.. and your good to go.
Regarding alignment. Do it yourself. Had professional's align mine 3 times. None of them got the prop centered in the stern tube or twigged to the real sorce of the problem. Waist of time and money. It's not hard it's just a question of you putting as much time as you need into it.
I will post a link my massive thread on this. Skip to the end for what fixed it.