[C320-list] Potable Water filter and Bilge Pump

[Jack Brennan]

The problem with the diaphragm pump is that it is only rated maybe 250 gallons an hour, which translates to 100 or so in real life. It wouldn’t take much of an emergency for it to be overwhelmed.

I use an automatic 500 gph Rule that runs for a second or so every few minutes to detect water. You can count on it removing maybe 250 gph. It works fine for drips from the stuffing box and occasional drips from rain storms. It also did well when my seawater pump started leaking badly.

As a backup, I have a 2,000 gph pump with alligator clips to connect it directly to the battery bank and a hose that leads into the cockpit. The advantage is that you can also lend it to a buddy boat if there is a problem.

Jack Brennan
Sonas, 1998 Caalina 320
Tierra Verde, Fl.





Sent from Mail for Windows 10

From: Stephen Cox
Sent: Monday, June 7, 2021 10:13 PM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] Potable Water filter and Bilge Pump


>      *   The pump itself makes a lot of noise.  I took a 
> video of it running and it has the sound.  Sounds like a 
> playing card in the spokes of your bike wheel but you are 
> doing 100 mph.  I can share the video if it would help.  It 
> is a model 37202-0000.  Are bilge pumps supposed to sound 
> like this or should I be looking to replace it before it takes flight
> 

It is a diaphragm pump so you would expect it to sound that way.  At least you know it is running.  The advantage of the diaphragm
pump is that it should handle bits and pieces floating in the water better than the centrifugal pumps, that tend to jam up with bits
of debris. (Been there, done that).

Once you have sorted the float switch/sensor issue, one way to reduce the noise would be to install a second quieter pump that comes
on before the original pump.  The original pump acts as a backup if needed and has the advantage of clearly announcing that it is
running, so you can go and check up what is happening in the bilge.  Two pumps have to be better than one if you are taking on
water.  I have done this using a pump like https://www.defender.com/product.jsp?id=4067759 which senses the presence of water by the
current drawn on the pump, avoiding all the issues of failed float switches.  A very faint whir is heard periodically which assures
you that it is functioning without being annoying.  I also plumbed in a completely separate disposal hose rather than trying to join
in to the existing setup.

Stephen Cox
Tegwen #1141