Sunday, September 13, 2015

ENGINE BED MODIFICATION


May 7, 2015 began the most difficult part of this particular engine installation:  modifying the engine beds.  The original Volvo Penta 2003T engine had been coupled a MS2V V-drive gearbox that had a 20 degree down shaft angle.  Not such a bad idea on Valiant’s part as it kept the propeller at an adequate angle so that it would have thrust even in pitching seas.  Throughout the many years from 1990, the engineering and obsolescence of the 20 degree down shaft angle gearbox took place: no one was manufacturing them.  The steepest down shaft angle available was a ZF 15 degree MIV gearbox that had been made by Hurth before they were bought out by the Italian company.  This meant that the engine beds would have to be reduced by 5 degrees.  I had prepared for this and had the “Gold Mine” from David:  almost 200 pictures with mechanical drawings showing the whole operation from start to finish.  Using David’s experience and mechanical drawings, my plan was to fabricate a template, in plywood, using the new Beta 50 footprint.  This would be laid over the existing 20 degree angle engine beds and new reference lines drawn to 15 degrees.  Compensation would then be made for the right angle aluminum capping rail  that would go on top of the fiberglass beds.  The engine beds would then be at their approximate correct angle.  I put in endless hours and sleepless nights fretting over how to get it done correctly.
On Gary’s advice, I contracted Wiwat Tachagulpongkon, a local businessman and former Chief Engineer in the Merchant Service.  He was bright, knowledgeable and had a good chandlery with a workshop nearby.  He would provide the mechanics and any other workers I needed.  I would supervise and direct the work being done.  The problem that I encountered right away was that no Thai general contractor had the experience to read mechanical drawings.  They are at their finest when they are using an angle grinder, hammer, chisel and screwdriver.  The job was going to be done by trial and error.  They were going to use the new engine as the ultimate template:  560 lbs of metal;  haul it on the beds, take measurements, haul it off.  This went on for weeks while they cut the engine beds smaller than  they had to be and then built them up with wood and fiberglass.
         The project was a comedy of errors with everything having to be done several times.  Supervision was absolutely necessary all the time:  leave them alone for a minute and mistakes were made.  It was the most difficult and frustrating part of the whole process.  Thais want to please but the mechanical side of their nature is one of general ineptitude.  Also, one must accept the fact that you cannot cause them to “lose face”.  It’s a delicate balancing act that I managed to pull off in spite of being demanding and meticulous.  Deng, the Thai worker that did all the cutting of the engine beds was a very hard worker.   It’s no easy task to sit inside a confined space cutting fiberglass, adding wood and then reglassing.
         The end result had to be that the engine would align with the shaft.  Some adjustment could be made by the engine mounting bolts but all that hauling on – hauling off had to produce results that were within Beta’s specifications.  As an additional safety factor and increased flexibility in the final alignment, I had ordered an R & D Flex coupling to be installed forward of  the engine  shaft coupling.  The final results of this will not be known until Sea Trials take place in January 2016.  Overseeing the installation, from beginning to end, has given me a complete understanding of the Beta 50.  After the the initial shaft alignment was taken and approved,  I made all the other engine connections.   I don’t ever want to go through that experience again on this planet with only one moon.
        On August 24th, the Beta 50 was successfully started and all systems and connections working.  There will be some dynamic adjustments


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