On July 29th our boat "Cirrus" was hauled out at Keehi Marine Center to be painted by Pacific Diversified Finishes (PDF). In addition to the painting they also performed a number of repairs on the boat. One of these repairs was the replacement of the vibration isolating rubber hose that surrounds the propeller shaft and connects the rear of the packing gland to the front of the tube that carries the shaft through the hull. This replacement required that the shaft be uncoupled from the engine and that the coupling plate on the end of the shaft be removed. Then the shaft could be moved toward the rear creating a gap between the engine coupling plate and the end of the shaft where the packing gland and the coupling hose could be removed. Then a new coupling hose was installed followed by the re-worked and re-packed gland. With that assembly complete the coupling plate was replaced on the end of the shaft and reconnected to the engine. There is reason to believe that the four bolts that hold the coupling plates together were not properly tightened.
The boat went into the water on Friday, August 23rd and motored a couple hundred yards to Slip D1 at Keehi Marina where PDF continued to work on it until Thursday, September 5th when it was released and we motored back to Ko Olina Marina. Good practice requires that the alignment of the coupling be checked after the boat has been in the water for awhile (the hull changes shape), but this was not done.
On Saturday, September 21st we got underway at about 11:00 am from our slip in Ko Olina with two friends from the mainland aboard. We motored out to the end of the channel and then sailed out a couple of miles into the ocean. At about 1:00 pm we turned back in toward land and ended up at Electric Beach where we anchored and spent a couple hours swimming.
At about 4:00 pm I started the engine in preparation for leaving the anchorage. There was a loud thumping vibration from the engine compartment that quickly became worse. I shut down then engine, got a flashlight and looked into the compartment through an opening that gives observational access to the rear of the engine and the packing gland. Water was gushing into the boat from around the shaft tube at a rate that made it impossible to see what was really going on. I then noted that both of my automatic bilge pumps were going full blast.
I got everyone into lifejackets and put out a MAYDAY call on Channel 16. Then we started pumping a manual bilge pump, and I moved the life raft into the cockpit. I then disassembled the engine enclosure so as to gain access to the area where the water was entering. I was quickly able to see that the coupling flange at the rear of the engine was separated from the shaft flange by about an inch and that there was only one bolt loosely connecting them. When I had gained access to the area and grasped the shaft that last bolt also fell out. Apparently the bolts had worked out one by one until there was only one left. At that point there was nothing to keep the two coupling flanges aligned and the motor just whipped the shaft around so violently that it tore the stern tube completely loose from the boat. Water was pouring in and had just about reached the floorboards at that point in spite of the pumps.
Later on I was able to find the final bolt that fell out and the nut and lock washer that went with it. The other bolts along with their nuts and washers had been washed under the engine.
I was able to line everything up and then push the fittings back together so that the flow was substantially reduced. The pumps were able to catch up and start getting ahead. I tried to stuff some rags around the shaft but that didn't work at all. Just holding everything in place was the best bet.
At that point the small fishing boat "One Shot" (with two expert salvage divers aboard) arrived followed shortly by a really big commercial boat "Pacifica". "Pacifica" had some underwater (plumber's) putty and one of the crew from the small boat and my mainland friend dove to try and use it to stem the flow. It didn't work too well so they ended up stuffing the opening with rags, rope and a plastic bag in addition to the putty. The combination of their efforts and the fact that I had found a better way to hold things inside reduced the flow to something like turning on a faucet at home. At that level the pumps were able to keep up. The water never got above the floorboards.
At that point a utility boat from Ko Olina Marina arrived and they came alongside to give us a tow back to the marina. Along the way back the leak kept getting worse but the pumps were still able to keep up. Fortunately it was a very quiet afternoon with almost no wind and very little swell. When we arrived back at the Ko Olina Marina we tied up at the fuel dock and made arrangements for a large electric pump to be standing by. I got on the phone to Les Vasconcellos, a diver I know, who I was sure would be able to do a more effective job of plugging the leak. It was almost sunset. Les arrived about an hour later and very quickly began work under water. It was harder to stop the water than we expected but he finally did it with a two-part epoxy made by Z-Spar called "Splash Zone". He also patched the hole from the inside and suggested a way to wedge the pipe in place to make it stronger. The patch did not leak at all, and the boat was completely dry while we waited for an opening at the boatyard so we could be hauled out and repaired.