How do I remove and refit the saildrive seal on a Hallberg-Rassy 34?

Replacing the main saildrive diaphragm on a Hallberg-Rassy 34 requires a haul-out, supporting and separating the engine from the saildrive, then removing and dismantling enough of the drive to fit the new rubber diaphragm. First read the saildrive identification plate and confirm which seal needs replacing: the watertight diaphragm or the external rubber fairing skirt, which is a much smaller job.

Identify the saildrive

Many original HR 34 installations have a Volvo Penta MD2030 engine with a 120S-series saildrive, but production changes and later engine replacements make the drive identification plate your starting point. Order parts against the complete drive designation and serial number, rather than the boat model alone.

The large diaphragm clamped inside the hull keeps seawater out. The thin rubber skirt glued beneath the hull smooths water flow around the leg; it is not the watertight seal. Propeller-shaft oil seals are a third, separate job.

Volvo Penta commonly specifies replacing the main saildrive diaphragm every seven years; confirm the interval for your drive. Neither engine hours nor an apparently sound visible surface establishes its remaining life.

Obtain the correct diaphragm kit and its fitting instructions before dismantling. Check which joint seals, O-rings and replacement fasteners it includes, and order the external skirt separately if necessary. You also need the workshop manual for the exact drive. Tightening torques, joint treatment and assembly details vary, so a generic torque figure is unsuitable.

Separate the engine

Arrange the lift with enough clearance beneath the saildrive and remove the propeller using its specified procedure. Photograph the installation, label connections and protect the cabin joinery along the removal route.

Work ashore with the boat securely supported. Isolate the batteries, shut off the fuel and support the engine and saildrive independently before undoing any mounts.

1. Remove the companionway steps and engine-access panels as necessary. On the HR 34, check how far the engine can move forward before disconnecting anything.
2. Drain the saildrive oil into a clean container and inspect it for water or metallic debris.
3. Disconnect the gear cable, cooling-water connection and any other connections that prevent drive removal. Disconnect engine hoses, wiring, exhaust or fuel connections only where the planned movement requires it.
4. Support the engine on suitable bearers or lifting equipment. Mark mount positions and record exposed thread lengths as reassembly references.
5. Undo the engine-to-saildrive connection and the necessary mount fasteners, then move the engine far enough forward to disengage the input shaft without loading it sideways.