If I read you right, you also have a very small "bilge" volume. Another
issue you might need to consider is the volume of the hose from the bilge
pump. If there is no non-return valve ( and I'd not recommend one for
conventional impellor type pump if your bilges get the same assortment of
stuff as mine do ) then when the pump turns off the hose contents runs back.
So the minimum volume of bilge which will work with a centrifugal pump, hose
and float switch is starting to be more than just a few cups-full!

Again not knowing the application, you might be better off with a float
switch for an alarm and a manual pump - most of them incorporate valves.

David

"Dazed and Confuzed" wrote in message
...
"P.C. Ford" wrote:

On Sun, 25 Jan 2004 12:07:50 -0600, Dazed and Confuzed
wrote:

I guess I wasn't too clear in my request.

My problem is not the height, but rather lack of height. Due to the
hull design,
I have no real "bilge" but rather only about 3" of collection area. I
need a
switch which activates at about 1.5" from the bottom of the "bilge" and
shuts
off at, ideally, zero. I can mount it to within about 1/4" of the
bottom. I have
not found a switch that activate that low.

Not sure that you will find one. Most bilge pumps, certainly the Rule
line does not pump lower than 3/4 of an inch.Lower than that, they
suck air and lose suction. It is a problem especially for boats like
yours that evidently have have flat bilges.

so I am finding out.

thanks


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