Hi Rick,

The boat is in Palacios TX. I had a good
telephone conversation with Peggie Hall today, and
she was very helpful. Based on that, I think that
the vent to the holding tank may be plugged, and
that there may be some buildup in the sewage
lines. The head flushes, but very slowly. When
you try to flush to the holding tank, it builds up
back pressure and flushes even more slowly. This
is all flushing with just seawater, as I have not
tried to actually use the thing yet.

The PO's had just installed the head when we
bought the boat. It could be that they replaced
the old pump style head because they were having
problems, and had not quite got the problems
sorted out with the new head before it sold.

Since some of the sewage lines are vintage 1985, I
think that I may replace them with new marine
hose, and replace all the clamps at the same time.
Now I've just got to find that pesky holding
tank vent, and find out why its not venting.

Don W.

Rick wrote:

One thing you might try is asking an experienced boater to look over your
head...

Where are you located???

Easiest way to figure that out is to remove the cover to the pump-out
and see if that fixes your problem. That should be plenty of vent to
decide if that's the problem. Then if it is, you can fix the vent.

Good idea! I'm so green at this marine head thing
that I don't even know where the vent _or_ the
cover is yet (sigh). I'll bet I'm fixing to learn
a thing or two here.

Don W.


Keith wrote:

Easiest way to figure that out is to remove the cover to the pump-out
and see if that fixes your problem. That should be plenty of vent to
decide if that's the problem. Then if it is, you can fix the vent.

Keith wrote:
Easiest way to figure that out is to remove the cover to the pump-out
and see if that fixes your problem.

It may work, it may not...'cuz the vent fitting on the tank is above the
surface of the contents, while the pumpout line comes from the bottom of
the tank. It would take considerable pressure buildup to create enough
pressure from the bottom of a tankful of waste to push the air ABOVE the
contents being displaced by incoming waste out a line that may be
several feet long, and vertical to boot.

Don, if you decided to try it, open the deck pumpout fitting VERRRRY
carefully...'cuz if your tank is seriously pressurized, it could produce
a very unpleasant geyser. Any pressure will produce at least some
outgassing (hissing) when you open the cap, so you won't have to try
pumping the toilet to know whether the tank vent line is blocked.

--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://shop.sailboatowners.com/books...ku=90&cat=1304

Peggie Hall wrote:

Don, if you decided to try it, open the deck pumpout fitting VERRRRY
carefully...'cuz if your tank is seriously pressurized, it could produce
a very unpleasant geyser.

Uh yes... That would be... unpleasant. I'll be
careful whatever I do. Right now I have to figure
out where the vent line output is. Any clues on
where to look?

Don W.

Don W wrote:


Peggie Hall wrote:

Don, if you decided to try it, open the deck pumpout fitting VERRRRY
carefully...'cuz if your tank is seriously pressurized, it could
produce a very unpleasant geyser.


Uh yes... That would be... unpleasant. I'll be careful whatever I do.
Right now I have to figure out where the vent line output is. Any clues
on where to look?

The vent thru-hull should be just below the toe rail near the tank...but
because people do strange things in their efforts to direct odor away
from the cockpit or portlights, it could be anywhere on the hull, even
the transom. Easiest way to find it: it'll be the smallest diameter
line coming off the tank, either on the top of it or at the top...follow
it to the hull.

--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://shop.sailboatowners.com/books...ku=90&cat=1304