Sunday, March 14, 2010

The Story of My Life

Some problem arises (In this case -- with the boat race prep.) and a campaign is mounted to address it. Which quickly gets out of hand, and is followed by:

  • Major effort
  • Major time commitment
  • Major expense
  • Stress
  • Frustration
  • Concern
This is followed by resolution, where the casual observer might be inclined to remark that, "It looks pretty much like it did before you started."

A case in point is the propane delivery system for the stove already discussed in a previous blog. Initially, it seemed to be ok, but a crimp on one of the hoses was rusty so we (Ric and I) decided to replace  it. Since we also wanted to clean the cockpit locker where the tank is stowed we pulled the tank and took it to be topped off. While the tank was out we cleaned the storage space, replaced the rusted hose and put a couple layers of zinc anti-rust paint on the pressure regulator mounting brackets and the tie down hooks.

Finally, Saturday morning just after dawn on Kaneohe Bay, with all the pieces back in place, (And the stove re-mounted, after a complete re-building of the gimbal system.) it was time to just turn it on to be sure everything was working. (Did I mention the broken handle on the breaker switch that powers the propane regulator solenoid valve? That had also been replaced. So, we were good to go!) Well, you probably could see this coming. It didn't work.

The entire morning was spent tracing and solving the problem. First it was necessary to determine that the switch was getting voltage and that it was passing it on when closed. The next step was to check for current in the activated circuit. None. (By the way, I recently popped for a pricey clamp-on ammeter. (So cool. Exactly the right tool for the job.)  The next hour or so was occupied by slowly cutting the wiring apart looking for the problem and a minimally invasive resolution. (Short of simply replacing everything.)  Some time was spent with the expression E = IR, where E = 13, R = 12 and I = 0. In the course of this investigation a spare battery was used to successfully exercise the solenoid. Then the solenoid was activated using a spare set of wires that just happened to be laying around. Finally, in the face of overwhelming evidence, it was time to begin surgery on the installed wiring. The picture tells the story.

Even though the crimp on butt fitting was inside the shrink on rubber tube it had corroded in such a way that it would pass on voltage but not current. By the way, this is the second time I have seen this in the last couple weeks. It seems obvious now, but the shrink tubing is not effective in sealing two parallel wires. The little space between the wires leaks.

The offending joint was replaced with a properly insulated one and now everything works like a charm. And, you guessed it, the whole installation looks (and functions) pretty much like it did before we started.

1 comment:

  1. it all sounds so familiar to any handyman ;-))