Thursday, May 31, 2012

One Step Forward, Three Back

Sailcraft Boatyard, Oriental, NC
35 01.97 N 076 41.11 W

Well, with our work complete, we splashed Tarwathie this morning.  Our intent was to sail as far north as possible today, and attempt to put to sea Friday Night at the Chesapeake Bay.  A weather window from Friday night to Monday noon would just about get us to NYC by Monday.  

But those plans had to be abandoned.  After splash, the first item was to check for water leaks around the shaft log and dynaplate where we had done work.   No leaks, so far so good.  Next, we started the engine and checked for leaks were Dave and I had cleaned the heat exchanger and replaced some of the water hoses.  ALARM: looking below, I could see water streaming from the end caps on both ends of our head exchanger.  SHUT IT DOWN!

So now Tarwathie is temporarily rafted with another boat in the canal at the boatyard.  I took apart the end caps and inspected the area.   The aluminum water jacket is corroded and pitted so badly, that the rubber O-rings could not seal the gap.  I tried putting some Life Caulk in there.  Still leaks.

Consultation with Daryl at the boatyard gave me the bad news.  There were several temporary emergency fixes we might try, but they would all cause bigger trouble in the future.  The only real solution was to replace that water jacket. 

A call to Beta Marine, confirmed that they had the parts, but that the cost was $1219!   We have to buy a complete new assembly, jacket, heat exchanger, and end caps.

Triple ouch.  We thought that we had accomplished this haul out and projects with a very modest bill of $564.  But now we are into major hit territory.  

We have to wait until Friday afternoon for a new gasket for the jacket to arrive.  That means we'll definitely miss the weather window for NYC.

Oh well, it accomplishes nothing to get upset over things like this.  Stuff happens and some of those things are expensive.   

I'll have to think back to my maintenance history to see how much my lack of skill or attention contributed to the problem.  The heat exchanger and end caps are brass and the jacket is aluminum -- dissimilar metals seemingly begging for trouble.  They depend on the rubber O rings to not only seal leaks but also to prevent metal-to-metal contact.   It seems like a delicate design to me escalating the consequences of a slight misplacement of one of those rings to something very serious.  

The owner's manual says that I should be able to clean the heat exchanger myself, but I wonder now if that's wise.  A certified Beta mechanic would not make that mistake.

What else could Beta owners do?  They could coat the edges of the end caps with anti-seize (anti-galling) compound to prevent galvanic corrosion between aluminum and brass.



3 comments:

  1. Dick - for what it's worth I wonder if teflon tape might help. I've got a Beta 28 on These Days II and might find myself in the same position down the line so I'd be interested in hearing what Stanley thinks of that -

    Good Luck - and faire winds!

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  2. Dick - a reliable engine must be very important to you guys so new sounds like the way to go.

    I was able to repair a corroded cast aluminum water cooled exhaust manifold using an aluminum / zinc brazing rod. It takes a oxyacetylene torch to get the aluminum to the 735 Deg F required. But the repaired surface was very hard and machined to a smooth flat surface which did not leak against the gasket. The only practical alternative for me would have been a new engine.

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  3. On the Perkins on Satori we found a aftermarket jacket that was a direct fit and much better than the original. It was really beefy. I cannot remember the name but I wonder if anyone has made the same for the Beta. Ken

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