My Favorite Head—The Blakes Lavac Toilet
On my own boat, I would install a Blakes
Lavac head. Built in Britain (www.blakes-
lavac-taylors.co.uk), they are unique in that
they have virtually no moving parts and thus
nothing to go wrong. In fact, I’ve installed
quite a few of these on boats that are easily
topping over 100,000 combined cruising
miles, and—to the best of my knowledge—
there’s been only one clog! Now that’s a head
you don’t have to think about. As I write this
(2007), the only U.S. distributor for Blakes
Lavac heads appears to be St. Brendan’s Isle,
Inc., of Green Cove Springs, Florida.
Figure 21-2 shows the plumbing arrange-
ment of the Blakes Lavac. This schematic is
based on the old days, when you could dis-
charge overboard. Today, the discharge is
into a holding tank. The toilet bowl itself is
part of the flushing mechanism. The lid has
a gasket all around. When closed, this seals
the head and allows you to pump a vacuum
in the bowl, which is the secret of its func-
tion. To flush, close the lid (#5 in the drawing)
and stroke on the pump. This pulls water and
air out of the toilet bowl (2) along with any-
thing else that was in the bowl. Everything
exits the hull through a seacock (4) or enters
the holding tank. Because the bowl is sealed
airtight by the lid, the vacuum then sucks
in fresh seawater to refill the bowl (1).
That’s it. There are no valves, flappers, or
other obstructions or mechanisms to get
plugged.Pumping a Vacuum
The pump is a simple, standard diaphragm
bilge pump such as the Henderson or
Blakes’s own. Any good-quality diaphragm
bilge pump of matching inlet diameter will do
fine. Pick a rugged one that is easily opened
for cleaning or repair, though both will be
infrequent.Water Levels
Another nice feature of the Blakes Lavac toi-
let is that after you’ve pumped to a clean
bowl, you can open the lid and pump again
with the lid open. In this case—with no vac-
uum formed—you pump to a dry bowl. You
can now close the lid, and without stagnant
seawater in the bowl, you won’t get that
vague rotten-egg smell from the toilet. YouChapter 21:My Favorite Head
Figure 21-2. Head operation (Courtesy
Blakes)
Figure 21-3.
Diaphragm pump.
(Courtesy Blakes)