Wasn't really sure how to title this episode on our boat so I will simply explain as I go. We hauled out in July 2021 and replaced the engine damper plate, the PSS shaft seal, the prop and the cutlass (not a cutlass as it's a brand but you know what I mean) bearing among other things. After several attempts to realign our Kiwi prop blades everything was going well. We had eliminated the engine vibration and corrected the over propping situation by decreasing the propeller pitch.
Two days ago I did an engine check to make sure everything was good for the Lady skippers race which is an annual event here in Cairns. My examination of the gearbox and shaft seal area under the aft berth made my heart stop. We had water in the area behind the engine at the PSS shaft seal and a mess of tangled wire and paper wrapped around the prop shaft.
What was immediately obvious was the fact the engine air supply hose which connects to a small 12 volt fan motor and provides fresh air from the stern vents; had come loose and wrapped itself around the prop shaft. This was no doubt done two days prior when we did our regular Wednesday Go Sailing event for the local community. It was blowing 15 knots and we were sometimes heeled over pretty hard in the social race. Of note, we did not know it had happened on Wednesday and parked the boat normally. No noise, no engine stutter or stall, completely invisible to us.
Unfortunately I had left my phone at home on Friday so I do not have photos of the event, only the aftermath.
Suffice to say, at some point the engine air supply hose, made of some sort of fabric and coiled wire, broke free from it's fasteners and when heeled over wrapped itself tightly around the prop shaft. The piece of pipe aft of the 12 volt motor was ripped from the housing and together with it's cable tie slid into the prop shaft.
My first examination of the event revealed water below the PSS seal which is normally dry and a mess of tangled wire and what appeared to be paper wrapped around the shaft. Most of it very tightly wrapped. A cursory examination showed exactly what had happened, with the 12 volt air supply motor now completely devoid of any piping aft of the motor. All of the pipe work aft of the air supply motor was wrapped tightly around the shaft. Water was dripping from the shaft seal and I was preparing to call for an emergency haul out, if the bilge proved to be full of water and thus the leak larger than it appeared to be.
Fortunately the bilge had little water which confirmed the leak from the PSS seal was minor - but still a leak. I then set about assessing how badly (and tightly) wrapped the material around the prop shaft was. My first instinct was to try to move the carbon stator (the seal) back from the stainless steel rotor to see if there was any movement. The carbon stator would not move and was already pushed hard back against the bellows by wire and paper wrapped around the shaft between the rotor and stator. So I had a wrapping of material around the shaft in front of the rotor and behind it next to the stator.
I decided to tackle the wire and paper between the rotor and the shaft coupling first. I figured I could get an idea of how easy it would (or would not) come away from the shaft there, before I tackled the carbon stator. It took 30 minutes of painstakingly slow work to remove the wire and paper between the rotor and the drive shaft coupling, but by using a pair of pliers and wire cutters I was able to remove the material. NOTE: when you remove a tightly wound piece of wire from the shaft by cutting it, it will spring itself free with a vengeance and cut into your hands when you do this. Be warned and wear gloves.
After this time I was still unable to move the carbon stator back as it was still jammed and separated from the S/S rotor (not surprising). So I set about slowly removing the material between the S/S rotor and the stator. This took 60 minutes and was highlighted by about four turns of the wire wrap being trapped underneath the stator bearing between the shaft and the stator. Each time I managed to pull a piece of wire from underneath the stator a new leak of water started into the bilge. I was more and more sure that I would need that haul out.
After 60 minutes of cursing, cutting wire and picking minute scraps of paper, I freed the last piece of wire from underneath the stator and it was now free to move back to and push against the S/S rotor. When I did so, a miracle occurred and all the leaks stopped. I held my breath for a few minutes and then moved the carbon stator back and fore to ensure it was still functioning - it was. I cleaned up the mess, dried the area underneath the PSS seal and with great trepidation, started the engine and moved it in and out of gear a few times. No leaks!
Now remember, this PSS seal is less than six months old and that may have helped, but I am very grateful right now, not to have done more damage. It is three days later and I check the boat everyday (I live 15 mins from the marina) and today we held a successful Ladies race (finished third). So far no leaks but I will be checking it every day for at least a month.
As I said no photos at the time. Here is a photo of the material I extracted from the shaft:
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