Technical notes
Short notes from the field on yacht and boat systems. In practice, manufacturer documentation and the system’s own conditions always apply.
In a watermaker that will stand idle for a long time, sea water left in the membranes can cause biological growth and fouling. The manufacturer’s preservation / pickling procedure protects the membrane; chemical, mix and contact time vary by model.
Pump selection weighs compartment volume, mounting position, hose size, discharge head and the electrical system together. The rated flow on the label is not enough on its own; real-world capacity is lower.
Frequent cycling usually comes from low pre-charge in the expansion tank, a small leak in the plumbing, a faulty check valve or a wrongly set pressure switch — and it wears the pump out early.
Overheating can come from low oil level, dirty or wrong-viscosity oil, a clogged filter, a relief valve constantly bypassing, internal leaks or insufficient cooling. Heat shortens the life of both oil and seals.
A spongy feel at the wheel, play, a change in the number of turns lock-to-lock and the rudder creeping on its own are typical signs. The system is bled to the manufacturer’s procedure; oil level and leaks are checked.
Odour usually comes from a blocked or undersized vent, a saturated carbon filter, old hoses that let odour through, waste left standing in the tank or leaking connections. Odour treatments without finding the source are only temporary.
Air usually enters on the suction side: loose or cracked fittings, a damaged filter seal, a clogged pre-filter, a low tank level or small leaks. The engine misfires, loses revs or stops; fittings and filter housings should be checked systematically.
It depends on usage and the water you are in; a visual check before every trip and regular cleaning during the season are recommended. Loss of cooling on the A/C or generator, rising engine temperature or little water from the exhaust are the first signs to check the strainer.
Next step
Share the system, your marina and what you need; if necessary we start with an on-site survey.