On Apr 28, 9:13*am, wrote:
On Tue, 27 Apr 2010 23:26:24 -0700, "nom=de=plume"





wrote:
"jps" wrote in message
.. .
On Tue, 27 Apr 2010 19:43:02 -0700, "nom=de=plume"
wrote:

I read the wiki on diesels, and I think I read that if a diesel is
running,
then it doesn't need a spark (e.g., battery energy) to keep running. If
that's the case, then it seems like you should be able to start a diesel
by
hand, assuming you have the muscle or leverage. So, in the former case,
even
if your battery died - perhaps got wet and shorted out - then the engine
would keep running. In the latter situation if the battery was already
dead,
you might be able to crank it to start it.

It's not that simple. *Motors have brains now and that brain often
controls both fuel, spark and timing -- and needs to be powered.

If your diesel was a throwback of many decades, you'd be right.

Interesting. No spark though on the diesel required or has that changed as
well? So, it wouldn't be possible to hand start it, but would it keep
running? Seems like it would be capable of generating it's own electricity,
much like a car engine charges the battery via the alternator. How many
amps/volts would be needed to retain its ability to control fuel, timing,
etc? Seems like it wouldn't require the same amperage that a starting
battery is capable of, so wouldn't a small, dedicated "engine function"
battery suffice?

Ok, I'm no diesel mechanic...

Even a car with an alternator needs some little bit of battery power
to get going. The alternator will not put out until you excite the
field, something I found out when I built thishttp://gfretwell.com/electrical/redneck_power.jpg
Hence the little Gel Cell.

Now back in the olden days when motor cycles had generators they did
build choppers with no battery, usually based on Triumphs, that only
had a tomato paste can sized capacitor stuffed in there somewhere to
hold enough power to get it going.- Hide quoted text -

- Show quoted text -

But the usually did that on the Brit bikes because the Lucas charging
system was too unreliable. The old saying about Joseph Lucas LTD was
true. They didn't call him the 'Prince of Darkness' for nothing.