Boat & Gear

Plumbing & Ventilation

Water in, water out and air through: the marine head and its holding tank, bilge pumps and float switches, fresh-water tanks, pumps and watermakers, and the ventilation that keeps a closed-up boat from growing mould.

2 guides

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How Does a Marine Toilet Work?

The flush cycle, the vented loop, the joker valve and the calcified hose — it is blocked, not broken.

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Plumbing11 min read

Bilge Pumps Explained: What They Can and Cannot Do

The GPH on the box is measured with no hose and no lift; a 25 mm hole a foot down lets in more than a real pump moves. Types, how many, wiring, float switches, and the pump-keeps-running diagnosis.

September 26, 2026

Plumbing11 min read

How Does a Marine Toilet Work? The Flush Cycle, the Rules and the Fixes

Manual, electric and composting heads, the flush cycle from seacock to holding tank, the vented loop, discharge rules, the vinegar treatment for a calcified hose and why the joker valve is a consumable — and why the toilet is never the culprit.

September 25, 2026

Plumbing & Ventilation: common questions

How does a marine toilet work?
A manual marine head pumps raw seawater in to flush and pumps the bowl out through a joker valve to the sea or a holding tank. It works when the seacocks are open, the joker valve is soft, and nothing except what has been eaten and marine paper has gone down it. Most failures are a calcified outlet hose or a joker valve that has stiffened with age.

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Anchor & Docking19Safety6Sailing7Fishing1Paddle & Water Sports1Electronics & Navigation18Marine Electrical2Boat Maintenance3Engine Systems3Boats & Motors1Galley & Outdoor1Deck & Covers1Clothing & Shoes1Boat Trailering1Where to Anchor15Sailing Itineraries12