Marine Plumbing & Ventilation

Marine plumbing splits into a few systems: bilge (getting water out), fresh water (potable supply and pressure), raw water (cooling and washdown), and waste. Match every component to its job. A bilge pump is rated in gallons per hour (GPH), but real-world output drops with hose length and lift height, so size up — a pump rated well above your bilge’s worst case gives you margin when it matters.

Hose is not interchangeable. Sanitation hose, potable-water hose, and bilge/raw-water hose are built for different pressures, temperatures, and permeation resistance. Using the wrong hose leads to odors, failures, or contamination. Below the waterline, use proper marine seacocks and double clamps on every thru-hull connection — this is a boat-sinks-at-the-dock detail, not a place to improvise.

Ventilation is the quiet half of this category. Cowl vents, solar and inline blowers, and dorade boxes prevent moisture buildup, clear engine-compartment fumes before starting, and keep the cabin fresh. A gasoline engine box in particular should be ventilated and blown out before every start.