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s/v Passport, Bianca 111
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49 Posts
Discussion Starter #1 (Edited)
I dropped the rudder yesterday after haulout for the season and was very surprised at what I found. Not all bad but surprised nonetheless.

Starting at the end of last season and all this season there has been a bit of a "thump" with a quartering wave pattern from the stern. Upon inspection after haulout last season I noticed a bit (1/4") when pulling the bottom of the rudder fore and aft (not so much laterally). However, with a bit of a heave, I could lift the rudder about a 1/4-3/8" which accounts for the "thump".

At first I thought the top bearings maybe needed to be replaced as the bearing being worn would let the rudder down a tiny bit. I replaced at the beginning of this season with new Torlon (no difference but good to replace the Delrin anyway). Now, after talking with some people I think there was a bake-a-lite or some other type of plastic spacer/thrust washer that sat between the flange of the lower bearing and the top of the rudder that just disintegrated or fell off. So my plan is to get some UHMW spacers and that should fix the "thumping".

Now the issue with the play in the rudder. I was expecting the bottom bearing was a plastic busing but to my surprise there is a bronze/stainless bearing race pushed into the rudder tube (ruder tube looks to be G10 or something smooth) and stainless roller bearings that ride on the shaft. The top bearing is the shaft going through a bronze fitting in the aft seat with a race on top of the seat. If you imagine this, the lateral forces are just handled with an interference fit between the shaft and the bronze sleeve but the real forces are to support the vertical forces with the race and cap wherein you'll find the new Torlon ball bearings.

Questions:

How to take up any slack in the bottom bearing? Sleeve on the rudder shaft? New Stainless or Torlon roller bearings (how can I get a size that may only be .0001" different from the existing bearings)? This looks like a customer metal race so I'm not expecting to replace it.

Ideas on getting the race out? I hate to open a can of worms or break something in the process but I feel this is the only way to test the fit with the bearing on the shaft and it would be good to re-bed it on the hull.
 

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I would say if it ain't broke go sailing. so many things that could go wrong if you remove the bearing race just to rebed. it is inside the rudder tube so if it is not loose what is to be gained by rebeding. it might be glassed in and if not loose it could last another 30 years just the way it is. what size is the shaft where the lower thrust washer would go, I would use bronze or titanium not plastic as you don't want it to swell up from being under the water. you can buy bronze thrust washers 1/8" thick for many shaft sizes
 

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s/v Passport, Bianca 111
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49 Posts
Discussion Starter #3
Well that is one option but I know there is play in the rudder. Usually when things like this start to get loose, leaving them loose accelerates the wear and damage.

I agree with the fact that removing the bearing race is the last option. Its seems to be in there very well and I don't want to disturb it or break anything trying to get it out. On the other hand there are only 3 pieces here and one or more need replacement/modification to make everything to the proper tolerances.

Any ideas on how to make the bearing system right again without removing the bearing race would be appreciated.

Thanks for the suggestion on bronze thrust washers too.
 
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