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Discussion Starter #1
I'm buying a 1968 Islander 33 which needs a new cutlass bearing. The prop shaft won't come out without taking off the rudder, right? So I believe the current owner, who is a good friend said he plans to cut off the back of the stern tube, twist and work the bearing over the shaft to the end. And the new bearing should go on this way too.

I have my doubts about this. Can you offer any help?

Thanks,
Brad
 

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Lots :

I think you are wrong on the rudder needing to come off to take out the prop shaft. Typically, there is a wee cut-away in the rudder to allow the prop shaft to come out. Classically, you don't need to take out the prop shaft in order to change the cutlass bearing.... if you take off the prop, the cutlass bearing just slides over the end of the prop shaft.

Even if the prop shaft could come out with the rudder on there, you normally have a big propshaft coupling on the inboard end of the propshaft, and you have to get that off first. I don't think you have to though.

What is commonly called the "stern tube" is vital to the prop shaft being supported. Don't let anyone take a hacksaw to it. The stern tube is normally threaded on its outboard end and on my ship, a big bronze plate threads to that. On other ships, there is a wee housing on there that holds the cutlass bearing.

Have you got a wee picture?
 

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Unless your cutless bearing is a lot different from the norm, it's going to be a royal PITA to even get it loose, much less sliding over the end of the prop shaft. Having just replaced a cutless on my own boat, it's the last one I'm going to bother with. However, I believe that every sailor should experience at least once the joys of replacing a cutless bearing!:D

Have fun, my friend!
 

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Actually, I was referring to getting the cutless loose from the shaft tube. Once it's loose, you're right, it slides right off because of the slop in the fitting. That's why we're replacing cutless bearings; that darn slop.:)
 

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Discussion Starter #6
So, if I don't have to remove the shaft to remove the cutlass bearing how would I get to the bearing without cutting off the end of the stern tube? There is nothing sticking out to get hold of...
 

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Well, then you will have to take out the prop shaft, then begin the long process of undermining the cutlass bearing from the inside with a Dremmel or something, or perhaps some sort of tool that expands into the centre of it.

Who in the name of sanity would ever put a cutlass bearing in flush with the stern plate?
 

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I 've done it twice on my Cal 9.2. Have to drop the rudder, remove the shaft, and then cut the bearing with a hacksaw and collapse it to get it out of the strut. A big job.
 

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I've done the job 3 times. Twice on my 28 an once on my current boat. Some things to keep in mind:

1. Any good marina has a hydraulic press that will extract the cutlass bearing without shaft removal. I've seen it done but that is not how I did it (because I'm cheap).
2. You have to determine why there is play. It is a sign of wear - in my experience due to engine misalignment or a bent shaft. Of course, if the bearing has been there a REALLY long time or had a lot of motoring, it will wear.
3. If you pull the shaft, look for scoring where it passes through the cutlass bearing or at the stuffing box. Replace the shaft if there is ANY scoring. If you're doing all this work, replacing the shaft (and engine coupling) is cheap money (~$300). To be honest, it was easier for me to just cut the thing out and install a new shaft.
4. To extract the cutlass bearing, I scored the inside of the brearing with a hacksaw and then cut it away (with a cold chisel) for about 1/3 of it's length. I extracted the whole thing with an extractor made from a 1 1/2" pipe, some washers, and 1/2 threaded rod. PM me if you want to see a photo of the arrangement - it's hard for me to describe, but it WORKS.
5. Store the new cutlass bearing in the freezer overnight and transport to the boat in a cooler. Freezing it will shrink the bearing slightly and make installation easier. Coat with dish detergent and PRESS the bearing into the strut using the bearing extractor that I described earlier. DO NOT pound on it. Use SS set screws and threadlock after GENLTY drilling a VERY shallow detent in the new cutlass bearing (once installed). Don't drill through the thing.

It isn't a really hard job, took me about 4-5 hours. At the same time, I also replaced the stuffing box with a PSS shaft seal. Again, it's cheap money (~$250) and it eliminates a wear point in the drive train. It is also much more forgiving of slight engine misalignment sine there are only two support points - at the engine and at the cutlass bearing several feet away. I have NO play at the bearing after 4 years.
 

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Discussion Starter #10
Sabreman wrote: 1. Any good marina has a hydraulic press that will extract the cutlass bearing without shaft removal. I've seen it done but that is not how I did it. (I'm omitting your comment about your being cheap. ;)) ...I am too, so it's ok.)

This hydraulic press has me wondering. I guess it is attached from inside the boat and pushes the bearing out toward the prop. I'm thinking this is going to be the answer - I hope so. And I'm not doubting anything you say, but I assumed the space in the stern tube had a reduced diamater forward of the bearing which would not allow anything to pass aft on the propshaft, and push out the bearing. Hopefully you are right. ...I hope, I hope. I don't want to spend 3 or 4 days, and a thousand dollars to put in a $20 cutlass bearing.

Thanks to everyone who offered their help so far, and any more help is greatly appreciated. I really am looking for a quick and simple repair. I've already spent 10 days in the boatyard getting the boat ready to make the trip to Key West. We considered doing the cutlass in the boatyard but it had just the slightest wiggle and I thought it would be ok for another year. So we sailed to Pine Island, tied it up, and left it for 2 monthes. But the friend that I'm buying the boat from is meticulous about his boats, insists the cutlass is causing vibration, and should be replaced.

Thanks Again ...and any more suggestions are appreciated
 

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I guess it is attached from inside the boat and pushes the bearing out toward the prop.
I did a quick web search for a '68 Islander 33 but didn't find one so I'm not sure if your boat is a full keel. From your statement, I suspect that it may be. If so, then the press won't work as far as I know.

For fin keeled boats with a spade rudder, the press attaches forward of the prop strut with an attachment on the aft side to hold it. It looks something like a pipe cut in half with a hydraulic ram. I can't find a photo of it in use.

For a full keeled boat, I'm not sure how the bearing would be extracted. It's possible that it can be used from withing the boat, but it's best for a yard to determine. If so, the labor shouldn't be much.

Good luck. Sorry if I misled you.
 

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On my ship, the cutlass bearing sticks out of the end of the stern plate. Last time I put a big pipe wrench on it and some WD40. It has a lock screw you take out first. Maybe I just got lucky.
 

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Discussion Starter #13
I'm fairly sure the boat is a swept semifull keel with attached rudder. This site won't allow me to send photo or link until I've posted 10 times. ...but i"ll try again, maybe this evening.

Thinking about having half an inch protruding beyond the sern tube, I see no reason why this would cause any problems, and could make the next cutlass change easier. ...hmmm....
 

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Discussion Starter #14
I've been talking to friends here in Key west about the cutlass bearing, as well as reading responses here on this list. I found a helpfull suggestion from a local sailor tonight, regarding pulling the shaft without removing the rudder. He said the rudder could be notched out to pass the shaft out. Patching the rudder would be a better than cutting the end of the stern tube and patching it. The stern tube is so important for holding the shaft, and I don't want it cut and patched.

So most likely, we will remove the shaft (notch rudder if necessary and patch), remove cutlass bearing using the hacksaw / cold chisel method, or hydraulic press method. I still have to learn more about the hydraulic press and if it will work on my boat. I guess it depends on the type of keel / rudder.

Here is a link to a photo of an Islander 33 (not my boat, but hull is the same).



...I tried to send the link but sailnet won't allow until I've posted 5 more times. Maybe seperating the link will work. (try adding the usual prefix to the following) sailingtexas.com/sislander33100.html
 
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