August 14, 2016

Other ways to start engines

JUST A FEW days ago I overheard a cruising sailor bemoaning the fact that he could not start his very expensive diesel motor because his comparatively cheap starter motor had failed. It reminded me of a column I wrote several years ago pointing out that cruising sailboats are rarely pure sailboats these days. There are very few that do not carry engines of one sort or another. The reason for this is that, even if you normally keep your boat on a mooring, sooner or later you’re going to have to maneuver in a harbor or marina, and small-boat harbors and marinas have become so congested that most are not navigable under sail in anything much over 20 feet in length.

It is actually possible to maneuver a boat in a crowded harbor by warping and kedging, or even sculling, as sailors have done for centuries, but we have either lost the skill or the will, and certainly the patience, so we now find ourselves far too dependent on the engine to get us out to where we can use the wind to sail.

And to get the engine started in the first place, too many of us are dependent on the electric starter motor. It would be a great relief if we could start our engines by hand, instead of having to rely on electricity, and indeed a few inboard diesels can be started by hand, but they are necessarily of low horsepower and fit only for small yachts.

Now, there are other ways to start engines. One way is to use a small hand pump to pressurize a tank of air that will spin the engine vigorously for a couple of minutes. Think what a blessing that could be when your battery is flat or your solenoid has passed on to its final resting place. There are clockwork engine starters, too, that you can wind up slowly and easily before releasing them to spin the motor over.

But these mechanically simple starting aids are not common and they are therefore expensive, so the great majority of sailors are stuck with electric starter motors. They are obviously not ideal for boats, but because most boat engines are derived from the ones landlubbers build in huge numbers for their cars, tractors, and generators, we are stuck with their method of starting them.

The one thing you can say for electric starters is that they don’t draw much energy from your battery. Surprisingly little, in fact, if the engine is working properly. For example, starting a medium-sized diesel will draw about 4,800 watts. That sounds like a lot, and it is, but even if you crank away for 20 seconds you’re taking only 2.5 amp-hours from your 12-volt battery. That’s about half of what a dedicated CD player would consume if it were running 4 hours a day. And even with a modest 30-amp charge, your alternator will replace that energy in less than 10 minutes.

Nevertheless, this is not the best way to start a marine engine. Salt water and electricity don’t get on well together, and most of us could well do without that sickening feeling in the pit of the stomach when you turn the key and nothing happens but a little “click” that foretells all kinds of trouble and frustration to come.

Today’s Thought
Simplicity, most rare in our age.
— Ovid, Ars Amatoria

“Dr. Livingstone, I presume.”
“Yes. Do you have medical insurance?”

(Drop by every Monday, Wednesday, Friday for another Mainly about Boats column.)

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