Bilge Pump

Published date: May 14, 2004
  • Boat Type: Boat Type

Because our boat is kept in a slip, I felt uneasy about not having
a bilge pump, even though it will probably never be needed.
Instead of installing pumps in each of the 3 main bilge sections
(separated by the fore/aft "stringers"), I just decided to put one
pump in the center section under the aft dinette seat
compartment. If water fills one of the outer sections, it will spill
over into the middle eventually, and be pumped out.

Note that the pump is an 1100gph Rule Automatic. This kind of
pump runs for a second or two every couple of minutes to check
for the presence of water. Only after the project was finished
did I realize that the noise made by this powerful pump was very
noticeable. I think it was made worse by the mounting method I
chose... I attached the bracket to the surface that forms the aft
end of the aft dinette seat, and it seems that this somewhat thin
fiberglass surface amplified the vibrations of the pump. I tried
installing rubber washers between the bracket and the wall, but
the noise was still bad enough that I knew the first mate would
reject it, as it would be very hard to sleep with this noise
resonating throughout the boat every 2 minutes. I considered
adding a manual switch or pulling the fuse to disable the pump
when we felt it wasn't needed, but of course there's a good
chance I'd forget to reactivate it.

The solution was to add a plain old float switch next to the
pump. Yeah, I know... adding a float switch to an automatic
pump is pretty silly. But it accomplishes my objective, even
though it wastes the one feature (no float switch needed) that
makes the automatic pump so expensive. Fortunately, I got it
from a friend, so I did not pay $90 for it.

The discharge tubing is 1.25", and is routed to a thru-hull in the
head storage cabinet (in the narrow space just aft of the sink). I
chose this spot to get the discharge port as high as possible, to
reduce the chance of water entering when the boat was heeled

The pump is extremely powerful... I put it in a 5 gallon bucket to
test the discharge line for leaks, and it emptied it in only about
20 seconds. 1100gph is probably overkill for this application,
but I guess it's nice to have that excess capacity in case it's

Published by: mike

Model Year: 2004


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