Wednesday, January 12, 2011

The Great Bilge Leak

After a lazy Christmas in Luperon, we made plans to leave Strolla and strike off into the Dominican countryside for a little exploring.  First, however, in order to leave Strolla we had to repair her to the point where she was able to be left.  Strolla had been struggling under a steadily worsening leak from her propeller shaft since leaving Florida.  By the time we limped into Luperon, we had water streaming into the boat at a rate of just under two gallons an hour, about 45 gallons a day, 360 pumps of the bilge pump.

The drawback wasn't that we had to be continually pumping out the bilge.  There were four of us to share that work load.  The drawback was that if we forgot to do it or weren't around to do it, the boat would sink.  This was why we'd put up with it for so long.  We'd always been on the boat.  Now, we wanted to leave the boat and couldn't.  The time had come to fix the leak.

The propeller shaft the the leak was coming from leaves the back side of the engine and runs aft, under the floor of the cockpit, to the stern, where it exits the hull to the propeller.  This space under the cockpit, between the engine and the stern hull, is a cramped cavity of wasted space over the spinning propeller shaft and the deep crevice of the bilge beneath.  Its dark and dirty and totally inaccessible.  In the middle of this no man's land, the shaft passes through a vertical stabilizing board fiberglassed into the hull.  The water was coming from somewhere on the back side of that board, impossible to see from the cabin by looking through the gap over the engine, impossible to reach from above through the small circular access hole in the cockpit floor.

The only way to physically touch the problem area was to wriggle over the engine.  The gap there was just big enough to fit through, provided arms, head and shoulders were forced through in the proper sequence.  I stripped down to my shorts and put on an old coat left aboard from last Winter's voyage in colder climates.  With pipe clamps and screw heads tearing at the coat as I slithered by, I made my way in.  Very quickly, I got stuck.  I exhaled, planted my feet, pushed, gained a few inches, got stuck again.  I retreated back out into the cabin to recalculate.

It took several attempts before I finally figured out a winning sequence.  I had to enter left arm outstretched in front of me, head cocked to the side, then shoulder shimmy a few more inches, then raise my legs so that I was balanced on my stomach on top of the engine like a teeter toter and belly role forward from there pulling myself along with my arms.  

Once fully in, my thighs rested on the engine, my hands on the sloped sides of the hull, body suspended over the bilge in kind of a push-up position, horribly taxing, impossible to sustain for long.  Mark stood by picking his cuticles, offering the occasional word of encouragement, ready to help.

From this improved vantage point, I was able to gain a slightly deeper understanding of how hard the leak would be to fix, and not much more.  Satisfied that I seen everything I could, I began the laborious process of wriggling my way back out.  Sweat poured out of me.  My hands were slippery.  The first few inches came easy.  My bare, sweaty thighs slid smoothly over the engine.   

After that initial success, things took a turn for the worse.  I got stuck.  Braced awkwardly, arms trembling, sweat running in my eyes, I took time to think.  Sweat dripped steadily off the tip of my nose to mix its salt with the rising water in the bilge.  I tried to remember the entrance sequence so I could reverse it.  My strength was failing.  I tried to back out again, and then again after that with the same results.  I was getting desperate.  I exhaled and pushed.  I could hear the fabric of my coat tearing.  Something sharp was pressing hard into my ribs, just below the breast.  I couldn't move.  Forcing down a rising panic, I called for Mark to help.  Taking firm hold of my ankles, he braced his feet on the base of the engine, arched his back, and pulled.  I continued to push with my arms and wiggle.  Slowly, I began to move again.  

Finally, I was free, breathing huge gulps of air, soaked in sweat.  Mark was sitting beside me.  I drew him a diagram of what I'd seen and where I thought the leak was coming from.  We discussed what to do.  It was obvious.  We'd have to borrow a saw from someone and cut a larger access hatch.

We took the rest of the day off with the resolution that we'd start looking for a saw tomorrow.  The next morning, however, Mark suggested an alternative.  He would try crawling in to the leak.  He was smaller and slighter than I was, not much, but it might be enough.  I rubbed the bruise on my ribs thoughtfully.

"Have at it," I smiled.  "I'll even stand by to pull you out when you get stuck."  Mark stripped down to his bathing suit and I handed him my coat, now black with accumulated grease and diesel and grit.  We reviewed the entrance sequence again, and in he went.

It was easier for him, but only a little.  After I'd helped pull him out, he had the same painful bruise on his ribs and in the same place as mine.  We figured out it was a pipe clamp causing the bruise and rotated it out of the way.  

The leak, it seemed, was coming from a pipe fitting on the forward side of the stabilizing board.  The water was then backing up through the board to leak out the hole on the other side.  After much lengthy discussion we settled on two alternative plans:

The right way - Cut the access hatch as planned.  Detach the propeller shaft from the back side of the engine. Detach the rudder from the back of the boat.  Slide the whole propeller shaft backward to create enough room to rework or replace the pipe fitting.  Reassemble everything.

The wrong way:  Send Mark back in over the engine with a small screw driver and some strips of plastic grocery bag.  Jam as much plastic bag as possible into the hole on the backside of the stabilizing board to plug up the leak.  Fashion a stopper out of some strips of rubber and a pipe clamp.  Snug the stopper up against board to keep plastic bag from working its way out.

Mark had the leak stopped an hour later.  We let the boat sit the rest of the day and then checked the bilge.  No water.  We ran the engine in idle for an hour and let the boat sit overnight.  No water.  We put the engine in gear and ran it in reverse, pulling against our anchor for half an hour and then let the boat sit the rest of the day.  Still no water.

The next morning, we walked into town to catch the first of a series little vans called "guaguas" (gwa-gwas) that would take us away from the coast and up into the mountains for New Year's Eve.

2 comments:

  1. I too have had "Yanmar" deeply imprinted on my chest, and have also, on several occasions come close to putting in a large inspection hatch in the cockpit sole - it isn't a big job and i don't know why I didn't do it. Remember if you do drop the prop shaft back, it doesn't have far to go before it hits the rudder. Are you sure it's not leaking at the stuffing box and the water running so that it looks like it's coming from somewhere else? You probably know this but: The stuffing box requires two large stilsons, or pipe wrenches. there's a smaller lock nut around the shaft that you back off, then you tighten up the larger nut which has the waxed packing thread inside, until water it is dripping just occasionally from the shaft, then tighten the lock nut back up.

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  2. Pete, your way of fixing the problem is not the wrong way at all. It's the Ver Pleog way. Gotta put a positive spin on it bud.

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