Head

After looking at various options I have decided on the Lavac head. The bowel is evacuated by the vacum generated by the Henderson manual bilge pump that mounts separately on a bulkhead; there are no other moving parts. 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 and rinse water is simultaneously drawn in at the top of the bowl. To prevent any chance of back-siphoning raise the toilet so that its rim is above the boat's waterline.

The 1.5 inch discharge line will have an electric discharge pump to evacuate the holding tank overboard when offshore. This line must have a vented loop to prevent back siphoning. The pump out line will be a separate line independent from the overboard discharge line. The schematic on the Lavac website also shows a ¾ inch hose bib rinse out line for the holding tank. Lavac

By using the same Henderson model for the cockpit mounted bilge pump one spare rebuild kit can service either one.