Where are the seacocks on a Hallberg-Rassy 34, and how should I service them?

On a Hallberg-Rassy 34, look beneath the heads basin and around the toilet, beneath the galley sink, and at the engine's seawater intake; trace each hose to locate its valve. Exercise accessible valves regularly and inspect the complete through-hull, valve and hose-tail assembly at every annual haul-out, replacing anything with porosity, cracks or leaks, or unreliable operation.

Find and label seawater connections

Check access and hose routing first. Before a hose or toilet connection fails, you need to know which handle shuts off its water supply. Equipment additions and previous refits can change the number and position of valves.

• Heads: follow the toilet's small seawater inlet hose and larger discharge hose beneath the surrounding lockers or sole panels. Find the washbasin drain separately. If a holding tank is fitted, follow its discharge plumbing to check for a separate tank outlet.
• Galley: follow the sink drain through the cupboard below, checking behind shelves or removable panels.
• Engine cooling: trace the hose backwards from the seawater strainer. If cooling water enters through a saildrive, the shut-off valve is at the drive; there may be no separate hull fitting.
• Additional equipment: trace any seawater supply to a fridge condenser, deckwash pump or other fitted machinery.
• Cockpit and deck drains: inspect their hoses and hull connections, including those reached through cockpit lockers. Check whether each connection has a valve.

The HR 34 and the later HR 340 are different models. Do not use an HR 340 fitting diagram to locate your valves. Transducers, exhaust outlets and tank breathers are also hull openings, but they are not ordinary seacocks.

Check valves without forcing them

On a conventional quarter-turn ball valve, the handle normally lies parallel to the flow passage when open and across it when closed. Check this against the valve itself, particularly if a replacement handle has been fitted.

Move each handle through its full travel. It should operate positively without an extension bar. A moving handle does not prove the valve seals: internal damage or a failed spindle can leave the passage open.

Operate sound valves several times through the season. If a valve becomes stiff, support the assembly and apply gentle hand pressure. Stop if the valve body or through-hull moves.

Remove hoses, dismantle valves and replace underwater fittings only when the boat is ashore and securely supported.

Inspect the complete assembly ashore

A seacock installation comprises the through-hull fitting, shut-off valve and hose tail. Inspect all three. A good valve attached to a weakened threaded fitting remains a serious defect.