On Mon, 13 Jul 2009 19:49:41 -0700 (PDT), Frogwatch
wrote:


Questions:

1: Is the noise of the honda due to its exhausting into air?

Just part of it. There other mechanical noises, some no doubt due to
the high revs needed - not much low-end torque in these things.
There are harmonics elements thrown in too.
Biggest problem I see is that they are air-cooled. That also limits
sound-deadening cowling.

2: Dont people who use these already have a diesel engine that should
power their alternator (seems not to be the case).

Some with inboard diesels do heavier duty alt setups, but usually
space available and the amount of work involved in a hot hole prevents
it, so they end up with the Honda gensets as a path of least
resistance.

3: Is it outboard powered sailboats that have these problematic
generators?

Not exclusively, but most OB powered sailboats are hampered by weak OB
alts. 6-10 amps max for the 10 hp range, and that's probably reved up
a bit. Solar and wind can fill some gaps, but there are many of those
Honda gensets on boats.
Just seems that water-cooled powerhead on the OB can be put
to more use.

4: Would the problem be alleviated by exhausting into the water via a
water lift exhaust as most inboard diesels do?

Don't think it's practical due to the usual distance the genset is
from the water and back pressure issues. Besides, that's only part of
the problem.

The most common sailboat outboard these days is the longshaft 9.9
Yamaha, a great motor. Seems like the best option might be a
switchable alternator, high output for charging only and low output
for charging and powering the prop.
Could this be done by only changing the voltage regulator? This
option might be a LOT cheaper than buying the Honda Gen.
Vic, this might be a good thing for you to pursue. I am not too
familiar with modern voltage regulators or modern alternators but they
cannot be that complicated. You might have a winner here. However,
wouldnt you have to run the OB at slightly higher RPM than idle for
real charging?

No doubt, but it would still be considerably more quiet and capable of
producing amps than the Honda gensets.
I don't want to pursue this - don't know anything about electricity,
or the mechanical engineering stuff.
Just tossing it out because when I get a boat this would be an
attractive auxiliary, seeing as I might want to occasionally run A/C
in Florida or other hell hot places.

UNFORTUNATELY (fortunately from my employees perspective), I suddenly
came up with this idea for x-ray optics for mammography (now where'd
that come from). I knew for awhile it might be possible but never
looked into it enough. Now, I find there are roughly 10,000
mammography units in the USA each costing from $200,000 to $400,000.
If we could make these x-ray optics to be sold for $20,000 each, well,
$20,000 times 10,000 units is a big amount of money, enough to get
venture capital types interested. Kinda looks as if my idle time will
be soon filled.
I vowed not to support Obamanomics but something like this is bigger
than politics if it gives far better contrast and much lower radiation
dose for mammographies.

Cool. Good luck with that. Good to hear you got inspired by altruism
instead of money. Money usually follows anyway. Entrepreneurship
comes in all shapes.

So, I highly reccomend YOU pursue this idea of the alternator. Do NOT
furhter mention it here because you might be giving up patent rights.
If you need encouragement, e-mail me at ohara5.0#mindspring.com
(replace the # with @).

Thanks, but I'm too lazy to fool around with it.
And like I said, it's surely been thought of before.
I'll keep my good ideas secret - when I get one.

--Vic