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The Foolproof Head

The marine toilet, more feared by most boat owners than a cantankerous engine.
One of the most vilified pieces of equipment aboard our boats is the toilet—or as most sailors like to refer to it, the head. The old salts among us tend to cling to this bit of archaic nautical jargon to remind ourselves of the days when the only toilet facilities aboard sailing ships was to saunter up forward to the bow, or head of the ship, and let your backside hang over the bulwarks to do your business. Nothing wrong with tradition, of course, but I know a toilet when I see one.
After 23 years of working on and living on boats,  I've come to two conclusions. First, the only thing that's more likely to break down and be more disagreeable to work on than the inboard engine is the marine toilet. Second, the only thing more likely to sink your boat than the engine is your toilet. Like the engine, on most boats, the toilet commonly sits below the waterline and has sea water running through its various intricate and delicate valves and chambers. Most marine toilets built today look like they were designed by the same man who built the first steam engine. They hiss, gurgle, leak and plug up. If you pump too hard to clear an obstruction they may even blow up in your face!

The day inevitably comes when every cruising skipper has the memorable experience of attempting to repair a plugged or leaking toilet at sea. Between bouts of seasickness he works with scraped knuckles, covered to the elbows in sewage while the disassembled and unidentifiable toilet components roll around the cabin floor and into the bilge. The unfortunate fellow is often referred to as having something ‘not right in the head.” Facing potentially nauseating toilet repairs, some skippers have preferred to chuck the contraption overboard and march into the nearest marine store for a replacement. And who can blame them?

The diagram of the author's on board system shows the additional Y-valve he added so that the same pump that dispels waste from the commode and be used to empty the bilge.

Against my better judgment, I have gained far too much experience installing and repairing many different types of cranky marine toilets. Over the years I've experimented with everything from an electric head to a typical hand-pump model to a porta-potti to a simple bucket in a box. Eventually I discovered a practical, safe, and reliable toilet to install aboard my 28-foot sailboat, Atom. The toilet is called a Lavac and is made in England. Its design is simple and ingenious. The toilet itself has no moving parts—it operates by vacuum. It comes with a Henderson manual bilge pump that mounts separately on a bulkhead. A hose from the inlet of the bilge pump connects to the toilet outlet. The outlet of the bilge pump leads to a Y-valve directing the flow to the discharge seacock, or to the holding tank when the vessel is in inshore waters. Before flushing the toilet, the lid, which has a rubber seal under it, is lowered. By giving about 10 good strokes on the pump, a vacuum is created within the bowl, which sucks the bowl dry, and simultaneously draws rinse water in at the top of the bowl.

Since my cockpit mounted bilge pump is the same model as the pump supplied with the Lavac, one spare rebuild kit can service either one. I carry an extra rubber seal for the toilet lid. Another practical point is that a second Y-valve can easily be installed in the toilet pump inlet and another hose led from it to the bilge to allow the toilet pump to also work as a bilge pump. If you feel as I do, that for safety, your boat should have a hand-operated bilge pump mounted somewhere down below, then this is an ideal arrangement. The only maintenance I've done since installing this toilet six years ago is to occasionally pump some vinegar through the system to prevent calcium deposits in the hoses. It has never plugged and never leaked, so what more could I ask? The Lavac costs more than its competitor's poorly designed and overly complicated models, but I have found it was well worth the price.

The temporary-but-watertight bulkhead in the foreground keeps any errant leaks from the away from the rest of the interior. Not visible is the six-inch wooden box that elevates the commode to keep the pump system from back-siphoning.
Despite having what I know is a reasonably trouble-free toilet, I found that I was still concerned about accidental flooding, either through the bowl back-siphoning and overflowing or through a hose or seacock failure. To prevent any chance of back-siphoning I raised the toilet so that its rim was above the boat's waterline by placing it on a wooden box about 6 inches higher than my original toilet. This placed the toilets rim about 2 inches above the boats loaded waterline. To guard against any leaks in the plumbing system I placed a plywood bulkhead in front of the toilet reaching from the floor to above the waterline and just below the toilet seat. The bulkhead was screwed in place to make it removable for future maintenance and was made watertight along its edges with a bead of polyurethane sealant. The top edge of the bulkhead is trimmed with a narrow strip of teak. The bulkhead is placed as close to the toilet as possible and angled in slightly at the bottom to allow for comfortable seating. Whichever type of toilet you install, placing it behind a watertight bulkhead will give you added peace of mind and prevent unexpected disasters due to plumbing leaks.

The only real complaint I ever heard about a Lavac was from a crewmate who was prone to seasickness. With a Lavac you have to wait about 30 seconds after pumping before you can re-open the lid in order to give the vacuum enough time to bleed off through a small vent hole in the water intake line. Normally this does not present any problem, but on a rough passage around the South African Cape my friend was unhappily embracing the Lavac for the first time and noisily giving up her lunch, when she decided a little too soon that she was finished. She closed the lid, gave it the requisite 10 pumps and immediately realized she wasn't finished after all. To her horror she found the lid would not open no matter how many fingernails she broke in the attempt. The result was not a pretty sight.

James Baldwin is offline  
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