It's a good idea to wire the bilge pump directly to the battery so you
can turn off the master battery switch and still have the pump active.
Leaving the master switch on could result in a dead battery or fire if
there is an electrical problem anywhere in the boat.

There is really no need for a switch on the bilge pump. It should
never be turned off. If you want to pump out the bilge before it
reaches the pumping level, just lift up the float switch. You
probably already have your head in the bilge to look. You should be
looking at the water level anyway to minimize running the pump dry.

If you do need to prevent the pump from running for some reason, just
pull the fuse.

Definitely run a second hose and install an additional discharge. If
you get a big leak, you might need both the power and the hand pump.
If your boat has a flexible shaft stuffing box, as most inboard
powered sailboats do, you want lots of capacity. The hose breaking
will tax even an oversized bilge pump.

Buy good hose. Don't use the corrugated "bilge pump" hose. The
resistance of the ridges cuts the flow dramatically.

If the bilge pump outlet is low enough that any loading or flooding
can put it below the waterline, remember that it can turn into a
reverse siphon and sink the boat. Have a high loop with a siphon
break.

If your pump discharges are in the transom and you have a small bilge
sump, you may run into a situation where
the water draining back out of the hose raises the water level enough
to trip the float again. The system will then just cycle over and
over until the battery runs down. Smaller diameter hose may solve the
problem but reduces your pumping capacity, especially with a long run.
Some people have had good luck with check valves, others haven't. I'm
in the latter category.

Here's my solution to the bilge cycling problem:

http://home.maine.rr.com/rlma/Bilge.htm

--

Roger Long



"just me" wrote in message
...
IMHO, the best way is to keep them completely separate.
That way you have redundency.
Run a separate discharge line (of the proper diameter) and wire it
properly from the breaker panel.

--


(817) 265-2813 fax
wrote in message
oups.com...
I have a manual bilge pump in a Newport 27, and
would like to add an automatic electric one.

What is the easiest way to do this? Can I use
(at least some) of the hoses that the mechanical
membrane pump uses?

The membrane pump is mounted in the back of the
cockpit.

Can I put both pumps on the same hose, i.e. can I pull
water through an electric (rule) pump when using the
manual, and can I push water through the membrane
pump with the rule?

If not, what is the next best/simplest setup?

Thanks for help and suggestions,

Chris