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Hands up if you have never spent some minutes (in the best of cases) or a couple of hours (in the worst of cases) of your holiday time kneeling by the WC or, even worse, with your head in the toilet bowl or by the seacocks. On-board toilets or better, marine toilets, bring joy and sorrow to all yachtspeople. Joy, as there is nothing better than having a toilet within a few metres when you need one urgently. Sorrow, as when something goes wrong – which happens quite frequently – the necessary repair work is long-lasting, complicated and as unpleasant as you can imagine.

Nowadays a marine WC is part of any ship’s outfit, even small size ones, unless ship owners prefer the good old-fashioned way i.e. a bucket. This choice is agreed upon also by the great navigators of modern day who compete e.g. in the Vendée Globe. However, the greatest majority of sailors prefers, in such a personal aspect, to leave the “Moitessier-style” aside and focus on the marine toilet option in terms of comfort and convenience.

The external appearance of an on-board toilet is entirely similar to the one at home: bowl, toilet seat and lid. However, similarities end here. First of all a distinction must be done between manual toilets (manual toilet osculati.com) and electric toilets (Evolution electric toilet osculati.com). While no on-board power is required to operate the manual toilet hand-pump, the charge and discharge pump of an electric toilet is power-operated. Both toilets are smaller than household ones (except those installed on large boats) and, above all, the water and sewage charge and discharge system is totally different from that of household toilets.

Each toilet has two seacocks, an inlet seacock provided with a dedicated inlet hose and an outlet seacock, also provided with a special hose (bigger). Sea water is let in and sewage is let out through a hydraulic pump called charge and discharge pump. This is installed by the toilet and is similar to pumps used to inflate bike tyres. The pump is made of plastic and has a hand lever with two positions: water charging (marked by a warning sign) and discharging. Position the lever according to the chosen option, then operate the pump gently at least 5 or 6 times, both in case you want to let sea water in and out.

The pumps work in two stages. First the rinse water is pumped into the toilet bowl and then the contents of the toilet bowl are pumped out. Unless the system is provided with a holding tank, the content of the bowl is discharged into the sea. For obvious reasons a marine toilet should be used only during navigation, far from bathers or other boats and never in a port, where restrooms are usually available. The main difference between a manual and an electric toilet is the pump, which, in the latter, is connected to the on-board system and operated through a switch valve, like a flush toilet.  

Maintenance, in both cases, is not technically difficult but rather awkward due to the installation position of hoses, seacocks and pumps. Make sure pipes are unclogged and therefore do not throw anything in the toilet that may block inlet and outlet pipes such as diapers, Scottex paper or similar, chewing gum or butts. Always remember that fixing clogged pipes can literally ruin your holiday. Actually biodegradable toilet water may be used in marine toilets but I strongly recommend to avoid this to prevent even the smallest possibility of clogging. On the other hand collecting used toilet paper in a bag requires no effort. Of course, all these precautions are useless if the toilet is provided with a macerator. With this (electric) device, toilet paper won’t clog marine toilet pipes.

Having made this clear, the remaining maintenance concerns the hydraulic pump, which has to be disassembled and thoroughly cleaned at least once a year. Replace gaskets if necessary. Kits containing spare rubber parts are available on the market at low cost. A regular maintenance of the pump and consequent replacement of worn gaskets prevents most of working troubles. Just one last piece of advice: always keep on board a spare pump or at least a spare parts kit.