Horror stories of struts and shafts and alignments

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High Current

Stories to keep you awake at night :D

When I bought my boat a year ago, I noted some small cracks in the paint on the prop strut.  I sanded it away and found some hairline cracks, as well as some "pinking" in the metal.  The cutlass bearing had a tiny amount of play.  I put it on my to-do list but didn't end up getting to it last spring.  During the course of the summer, I also found a couple of the motor mount bolts had vibrated loose.  But as far as I could tell without separating the coupling (which was rusted / frozen on), alignment seemed OK.  Engine shake was no worse in gear than at idle, although that's not saying anything.  Fortunately, I sailed all summer without any major issues.
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With magnification:
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At haul out, the cracks had resurfaced through the new paint and the cutlass bearing was totally shot, so no more putting it off (not that I planned to).  I ordered a new strut from CD, new motor mounts, and set about removing the old shaft, which I had also decided to replace.  That's when the fun really began.

Pulling the stuffing box, I discovered the shaft was nearly resting on the bottom of the log, even while mated to the transmission and seemingly in alignment - likely because the worn cutlass bearing allowed it to sag (and also: likely the cause of the worn bearing).  It called to mind justinsteele's post a couple of months ago where the bottom of his shaft log was totally worn away.  I was lucky, and mine appears intact.
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However, some cracks in the fairing on the underside of the hull mean it must have seen some stress / vibration and I'm in for some grinding and/or fiberglass repairs to make sure it's still firmly attached.
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The shaft coupler was, of course, frozen on.  After exhausting all other options, a sawzall and some cutting fluid made short of work of it.  My advice:  if you know you're not saving the shaft, don't even bother trying to get it off the regular way.

Next up:  getting the shaft out.  The issue was clearing the rudder.  I had read that one can get the shaft out without dropping the rudder if the cutlass bearing is removed, but I didn't have a strut-pro.  The new strut has the bearing pre-installed, so as long as the shaft is installed before the strut there will be no need for fancy tools.  Worst case I could have pulled out the sawzall again, but I hoped maybe the wear would be enough to let me sneak it past.  No such luck, but when I pulled on it I could see the strut's crack widening!  A couple of good heaves later it split wide open and I could slide the shaft out easily  :shock:  :D
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There's nothing like the feeling of vindication after you've already decided to fix something...
Ben, #1050, 1990 Mk 1.5 std rig / keel

waughoo

Oy!!! That's moderately scary.  However, it appears you caught it in time to avoid any major damage (stern tube replacement comes to mind).  Keep us posted on the replacement of the strut and motor mounts.  I have motor mounts on my short list.
Alex - Seattle, WA
91 mk1.5 #1120
Std rig w/wing keel
Universal M35
Belafonte