While trying to trouble-shoot a cooling issue (see post under the "mechanical/engine" section), last week, my starboard engine, the good one, quit after starting successfully and running a few minutes earlier.. No start, even when I hit the parallel switch to bring in the other battery. What was worse, I couldn't power anything connected to the starboard battery bank. I gave up in frustration and went home.
Yesterday, same thing. No power on the starboard side. But the voltmeter showed the batteries, though not full, had sufficient juice to at least power accessories and make the engines crank. Thinking about things, I focused on a device that I had installed several years ago called "Marine Priority Start". It's advertised purpose was to sense when an unwanted drain was taking the battery down past a safe point. Hooked into the positive side, it would cut off any further drain until you hit the ignition key. As soon as I had installed it I did notice that the starter would hesitate and labor as I first turned the key; the device it seemed was trying to turn itself back on and pulling extra current. Maybe now, I reasoned, it had malfunctioned.
Indeed, it had. I removed the device from the circuit and hooked the positive side back to its normal configuration. Voila (or walla as some folks like to say)! Engine cranked and started up and the starboard side accessories were back in business.
Marine Priority Start is now on my no-priority-at-all list. It's a good concept (and maybe even works for some) and I hope is really useful in other applications. But it's off the boat now as punishment for giving me more heartburn on top of the stock market plunge! I noticed also that while it was once sold by West Marine, it's no longer on their shelves (they now sell something called a Marine Battery Brain that appears to have a similar function). Mine's in the dumpster.
Joel Albert, Potomac MD
"Charlie B" - 1988 32' FBS
Twin 318's/FWC/16x15 nibral props
docked Deale, MD
