--- In amphicar-lovers@y..., "Bill Connelly" <billiam@e...> wrote:
> I'm looking for an additional bilge pump for my Amphi. What I'd
like
> is a submersible pump with electronic water sensors built in. To
> avoid the on/off cycling that would occur from water sloshing
around,
> I thought it would be nice if the pump would have buffering
> built into the control circuit so that a 10 second delay would occur
> before turn on and something like a 5 second delay for turn off.
Does
> someone make such a thing or will I have to invent it?
>
> John Friese
>
> =-=-=-=-=-=-=-=-
>
> I have an automatic float-operated backup bilge pump installed in my
own
> Amphi, and you can see more details on the setup at
>
http://www.geocities.com/SoHo/8389/autosploodge.html or see it in
person
> this Labor Day weekend during Billy & Randy's Festival in Mays
Landing, New
> Jersey (see the Club's 'Events Calendar' at
>
http://www.amphicar.com/calendar.htm ).
>
> Fact is, the only times I usually take on more than a dribble of
water is
> when I have three or more fairly large adults and other gear in the
car, and
> at those times I usually just make a point of running my
still-functioning
> original pump every couple of minutes. I can easily see when to
shut it off
> in my rear view mirror because I have installed a bilge spout
"elbow" (see
>
http://www.amphicar.com/ads.htm#elbows for a really nice one). So,
my
> backup pump is really there just for added piece of mind. I have
tested it
> in the drink with a controlled leak at water's edge and it works
just fine
> without additional timers, turning on when the water level in the
bilge
> reaches about an inch.
>
> If the on/off cycling you mention above ever became an issue, which
it
> hasn't, I would simply operate the original pump for a couple of
seconds and
> that would take care of that, since the original pump's inlet filter
is set
> lower than the backup pump's and would tend to pump out any of the
water
> likely to cause the automatic pump's float switch to rise. With
that said,
> this just describes my own preferences and experience in the matter.
> Functionally, my backup pump is really just that: a "backup pump".
My
> original continues to do the real work. That said, I can also
appreciate
> how one might want to install a second modern pump as one's MAIN
pump, with
> the original still there as the backup (you DO want SOME backup
pump,
> right?). In that case, I suppose that on/off cycling might be an
annoyance
> issue. What one could do in that case would be to install one's new
> float-operated pump and run its float switch through some kind of
timer
> circuit. The same folks who can supply you with the bilge blower
fan
> timer's vacuum tubes, the Amperite Company (see
http://www.amperite.com/ ),
> can also supply you with various other timing switch equipment for a
variety
> of applications. Whatever the specific timing equipment chosen, it
should
> probably enable the pump to operate not only some period of time
after the
> float switch opens, but also after it closes too, or you might find
yourself
> with the same on/off cycling...just with more water in the bilge.
Or, you
> could perhaps choose a timer that only continues timing towards
startup if
> the float circuit remains open.
>
> The only real problem I see with any such timer system is that it
needlessly
> complicates matters, saddling you with more delicate stuff to
possibly go
> wrong. Whatever timer system might be installed should certainly
have a
> manual bypass feature.
>
> ~Bilgemaster~
Hello,
It's true, my concerns about on/off switching are more theoretical
than actual. I've seen stories about the float switch type pumps
having sticking floats and would suspect the "sloshing" issue would
be a more common problem in a faster boat. That's why I thought
someone would have come up with a more sophisticated switch then a
mechanical float. I am a general believer in modern electronics to
solve these issues. The kind of timer circuit used in the bilge
blower circuit is hopelessly antiquanted and trouble prone by today's
standards and I figured someone might have a little timer chip
encapsulated in epoxy that would do the whole deal.
John Friese
