Forums General Discussion Upper rudder post bearing

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    • #222151
      typhoontye
      Participant

      Hello all,

      I had a ‘dis-quieting’ experience on a recent overnighter. Everything was wonderful until the wind slacked off a bit, and we had some sail slatting, etc.. Then I started to get a knocking sound that may or may not have been related to intermittent loads on the rudder in the sloppy seas. It was pretty significant as it drove the off-watch crew from the aft cabin bunk to the main cabin due to the racket. I put my hand on everything I could readily reach in an effort to feel this obnoxious percussion, but to no avail. After a couple of hours, the knocking disappeared, perhaps coincident with freshening of the breeze.

      In trouble shooting today, I looked at the rudder post upper bearing and found it to be sloppy when I moved the wheel about. I can’t point to this as causal, though it might be. In any case, on my boat, the rudder post passes through a solid structure at the upper end, terminating above said structure where the quadrant is fastened. There is a bushing at the contact circumference of the rudder post where it passes through this structure. The bushing appears to be made of plastic, perhaps PVC. It is worn, it appears, and damaged. Some of the bushing is simply gone (about a third of it), and debris of the color and material of the bushing was found just below this point, in the vicinity of the rudder post stuffing box.

      So I guess my question is three-fold: 1) Has anyone experienced the dis-quieting knocking noise, 2) Could it be the rudder post upper bearing/bushing, and 3) Anyone replaced the rudder post upper bushing?

      One other piece of info. The vessel was recently out of the water and I inspected the lower rudder post shoe, and it appears to be in good shape. I shook the rudder and could not see any axial play. But then again, forces generated by the water are much greater than I could muster manually.

      Any responses are, as usual, much appreciated.

      David Tye
      Blue Moon

    • #222172
      cstewart
      Participant

      Sorry, I have had no problems or experience with the rudder post, but I did grease mine after your post. It’s the only thing that hasn’t broken yet.
      Charlie
      OneEighty #54

    • #222173
      john stevenson
      Participant
      Any of us who have not checked on the bushing will probably find it has slipped out of place as mine has done repeatedly (http://www.svsarah.com/Sarah/ewSimpleRepairs.html#Rudder_Post_Bushing).  Even with it out of place as shown in the picture on the my web page, I never experienced any noticeable movement of the rudder post.  I just push it back in place every few years.
      I've never replaced the bushing, but I suspect it is not something Pearson fabricated, but merely the adaptation of a fitting available from some commercial outlet.  If I ever have to replace it I will start looking in the McMaster-Carr catalog.

    • #222175
      RichCarter
      Participant

      I’ve never had a problem with this rudder bearing and was wondering why.  I have an Autohelp autopilot with a separate quadrant that is mounted just above this bushing.  This likely prevents the thing from slipping out.  I wonder if folks couldn’t just clamp something above the bushing to hold it in place; perhaps a hose-clam would do.

       

      Rich

       

    • #222200
      typhoontye
      Participant

      Thanks for the responses.  Mine looks a lot like the one in John’s photo, though white in color.  It was originally held in place by small brads driven through the upper flange into the beam itself.  Also, mine is missing a fairly substantial amount of material on the bearing surface (cracked out/disintegrated).  I will attempt to find some thin-wall PVC  tubing at the box store that has an ID of 1.5” to match the rudder post.  Then split the tubing, insert over the rudder post, tap into place, and install a hose clamp or clamps to prevent it from coming out.  I’ll let y’all know how it turns out.  Gotta’ get this and other projects complete in time to depart later this month for the Key’s and Bahamas!

       

      David

       

    • #222233
      madsailor
      Moderator
      The material is teflon sheeting, I think.  It's available from McMaster  Carr. PVC won't last as long. 

      Bob

    • #222238
      JodyandStephen
      Participant

      I am glad to hear this as a topic. Halfway through crossing the Pacific in 2016 I started to hear a dull knock from the steering mechanism, turned out to be this bearing. This occurred in relatively strong trade winds and strong port quarter seas. I reseated the plastic bushing as best I could and occasionally heard a slight noise from it. Subsequently, here in Australia I had the rudder checked externally to make sure there was not a problem further down the rudder shaft- all good, and there hasn’t been the same sensation – now 4 countries later.

    • #222241
      typhoontye
      Participant

      Real glad to hear this response.  I too was worried about something more serious, but hopefully this is it and I can find a suitable material to replace mine.  Our ‘noise’ also went away, but haven’t had too much sailing time since this happened, so I don’t really know.

       

      Bob stated that he thought the material to be Teflon.  Maybe it is, but I’ve not seen Teflon like this….formed to a specific diameter.  Where it broke out, the fractures are sharp, like a hard plastic would break.  I think Teflon wouldn’t fracture like this?  I’ll research the home store today and look at McMaster Carr as well.

       

      David

       

    • #222243
      madsailor
      Moderator
      If it's teflon (as I think mine is) it came as a sheet that was cut to the circumference of the shaft and slid in.  Hose clamps applied.

      If you think the shaft is wobbling, though, make sure the packing gland is tight or doesn't need new packing.  That would be the only other place it could rattle.  Well, that and the auto pilot yoke and assembly – I've seen them wear and rattle.

      But if you know the clearance around the shaft, a bit of teflon will do the job.

      Bob

    • #222257
      typhoontye
      Participant

      I removed the old plastic bushing and it measures .055 in thickness, close to 1/16”.  Checked McMaster Carr, and they sell plastic bushings, complete with the flange, but the thickness of the material is 1/8”.  I would have to bore out the hole in the beam I believe, which would involve dropping the rudder.  Not going to happen right now.  They also sell Teflon sheet in 1/16” thickness.  I have to think on this, but I believe I’ll purchase some Teflon sheet (about 13 bucks) to have on hand during my upcoming cruise.  Meanwhile I’ll reinstall by broken plastic bushing and press on.  If the bushing proves to be a problem, I’ll at least have material on hand to effect a fix. I’m getting short on time and this is a stop gap solution.

       

      I did look at the packing gland (rudder post stuffing box), and it looks good and is not leaking water.  I’m afraid to put a wrench on it for fear of breaking something, probably not a good attitude.  I am carrying packing material and appropriate wrenches and will keep an eye on this.

       

      Autopilot stuff appears pretty tight.  If the problem recurs, I will clean out the lazarette under way, remove the peg board, climb in there, and have a good look with a strong light.

       

      Thanks to all for the responses and advice.  It was very helpful!

       

      David

       

    • #222265
      typhoontye
      Participant

      Update: I bought a piece of plastic pipe from the Lowes.  It is a tailshaft, I believe, intended for the drain circuit of a kitchen sink.  This piece consists of two separate diameter pipes, the larger of the two intended for a smaller adjacent piece of drain pipe to slip into it.  The larger diameter segment of the piece I bought is 1.5 inches ID, which is what I needed for the 1.5 inch OD of the rudder shaft.  I cut out the needed section of the pipe with a sawz all, then cut that piece longitudinally so that I could slip it over the rudder post without taking the quadrant and all the autopilot mechanism off.  The wall thickness of this pipe is somewhat more than the wall thickness of the piece I removed, so I was not sure it would slip into the hole of the beam.

       

      Back at the boat, I was able to pull the pipe apart at the cut I made so it would slip over the rudder post successfully.  I did not break or permanently deform.  It slid into the space between the rudder post and the hole in the beam just fine.  I left about ¼ inch of the new pipe sticking out above the beam and clamped that with a hose clamp.  So far, it looks good.  Whether or not it lasts remains to be seen.

       

      David

       

    • #222266
      madsailor
      Moderator
      Brilliant. Good job!

    • #222283
      typhoontye
      Participant

      One final thought on the subject, I would like to suggest a more optimum fix for this problem. Next Summer, I may execute this fix, when I change out my rudder cables, which have a few broken strands. The genesis for this suggested fix is my experience with a similar problem on my last vessel, a 1990 Caliber 33.

      On my Caliber, there was no rudder shoe at the bottom. It was essentially a standard post mounted rudder hiding behind a permanent skeg. Caliber corrected this on subsequent models, and installed a shoe at the bottom. But, my problem turned out to be at the top rudder post bushing which was pretty primitive, similar to the 424s. The symptom of the problem was steady percussive banging at high rudder loads, primarily when on a power reach with a lot of helm. It was very bad, shaking the entire boat. I worked with George McCreary, the designer of the boat, on a solution. After several discussions, we decided to look at the top rudder post bushing, which on the Caliber was a simple bored piece of quarter inch, or so, stainless, through which the rudder post passed. No obvious shaking or play at this point. But George suggested replacing this piece with a ball bearing assembly, which Caliber had started using on the 40s subsequent to my model. It was a pretty substantial piece consisting of a ball bearing with zerq fittings, mounted in a cast base of some sort. The assembly was slipped over the upper rudder post and bolted in place to a beam similar to the one on our 424s. I was not optimistic this would solve my problem, but it did. I was thrilled.

      Anyway, I am thinking of a similar solution on Blue Moon. Suitable bearings are available at McMaster Carr for around fifty bucks, and it would be a fairly simple matter to fabricate a mount for the bearing out of hard wood. Then slip it over the rudder post, and bolt it to the beam. Of course the quadrant would have to be removed first, and clearance between the top of the new assembly and the quadrant would need to be assured.

      Anyway, thought I would throw this out before I forgot about it.

      David

    • #222290
      unabated
      Participant
      Before I bought my 424, I owned a Catalina 30 Catalina. in their infinite wisdom they put the rudderpost through a fiberglass bushing in the lazaret which wore out quite quickly. Walk around any marina and look at the Catalina 30s on the hard,  grab the rudder rock it back and forth and it has a lot of play for and aft which means that the  top bushing is worn. their solution was to mix up a batch of west system epoxy with a graphite additive and squirt it around the rudder post and into the fiberglass bushing so it forms a bearing
      It’s all listed in quite a bit of detail in the west system handbook on how to do that. 
       
       but I was thinking about using the same process along with the epoxy and graphite to form a bearing right in the beam surrounding the rudderpost for permanent fix. 
      Alan
      #140
      Unabated 
    • #222294
      cbboat
      Participant
    • #222295
      typhoontye
      Participant

      Very interesting photos.  Thanks

       

      David

       

       

    • #222299
      Miss Kathleen
      Participant

      I had the same issues.

      PO owner, during the trip across the Caribbean, had to push the bearing back into place and added a hose clamp to prevent it from rising up. The problem that then developed was that rust from the hose clamp caused the bearing to seize onto the shaft and wear a larger hole in the wooden beam. This also resulted in the autopilot drive arm becoming sloppy.

      Solution – bored a hole in a large piece of plastic and bolted this over the original bearing (after freeing it from the shaft). Just removed the quadrant and slipped the new bearing block into place. Have not had any issues since and is as solid as a rock!

      Cheers

      Dennis

      Attachments:
      1. Rudder-Shaft.jpg

      2. Rudder-Shaft-Compl-2.jpg

    • #222303
      typhoontye
      Participant

      Super simple.  I like it. 

       

      David

       

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