describes C34 owners' head and holding tank upgrade projects.
Please contribute yours!
Fresh Water Head and Overflow Control
I got a little tired of the Head Overflowing when someone
forgot to leave the handle down. I decided to convert the
smaller starboard Fresh Water Tank to a dedicated fresh water supply
for the head. The starboard water tank is about the same size as the
holding tank. This is great because you reduce the risk of
overfilling the waste tank. I added a 1/2" Tee off the inlet
sea cock and put a 1/2" ball valve and a one way check valve on
the fresh water inlet side of the Tee. Then disconnected the
stabbed fresh water tank from the fresh water supply system and ran
a direct line from the water tank to the Tee. Then connected
to the head inlet line to the other side of the Tee. End result and
- I don't need to use the inlet sea cock. It stays shut. I
only need to open the ball valve to the fresh water tank.
- The head never overflows. The top of the head is is just
a little higher than the top of the water tank.
- The head odor disappeared or at least is better. You
don't have all those sea water microbes dying and causing
- We only use the large stern water tank for drinkable water.
We use it more and this keep things fresher.
Let me know if you have any questions (R
I just finished building a vent filter for the holding tank. The
breakthrough thought came from my wife, while we were discussing the
possibilities, and I asked what the filter medium could be.
She immediately suggested activated charcoal, which makes perfect
sense, and I was soon off to Hechingers for parts. I built a
U-tube structure with 2" PVC sanitary piping and 3/4"
elbow end fittings to connect into the vent tubing where it rises up
past the electrical panel in the aft-most cuddy on the port
side. The U is about 12" long, and 8"
wide, and is filled with a mixture of straight activated charcoal
and something called "Ammocarb". These came from a
pet store, where they are sold in bulk to people who own fish.
They are used to filter out the same noxious gases in fish tanks.
I have never seen the commercial product, and didn't know how big
the absorber bed is, so I figured that a bed that was 2" in
diameter by about 30" long should be fine. If not, I can
extend it by adding some more loops. The U also has a side tap so
that I can empty and refill it when the charcoal is exhausted.
The whole thing cost about $20 in parts,and about $10 for the
charcoal. And I can re-fill it very cheaply. I filled one leg
with Ammocarb, and the other with straight charcoal. It works very
well, and we now don't have to worry about stinking up a whole raft
of boats any more! (Ralph Caruso)
Important: The opinions expressed here are those of the
individual contributors to this page, and not those of the Catalina
34 National Association or Catalina Yachts, Inc. Additionally, this
material has not been reviewed by Catalina Yachts, Inc. for
technical accuracy. This page's maintainer cannot guarantee the
accuracy of this information or the desirability of suggested
modifications or upgrades. Please obtain assistance from a competent
marine mechanic or boatyard prior to making any significant
modifications to your vessel.