Which anodes are needed for a Hallberg-Rassy 46?
I'm ordering sacrificial anodes for my Hallberg-Rassy 46 before the next lift-out. Which ones should I buy, and do I need any inside the engine as well as around the propeller?
Answer
Your Hallberg-Rassy 46 needs anodes matched to its installed propeller and shaft arrangement, plus any hull, bow-thruster, engine or generator anodes specified by the equipment manufacturers. There is no dependable universal HR46 anode kit, so check the equipment and existing mountings before ordering, as propeller changes and refits can alter the list.
Check the shaft and propeller
The HR46 normally has a conventional propeller shaft, so start with shaft-drive components rather than ordering a Volvo saildrive ring. At lift-out, photograph the propeller hub, the shaft between the propeller and stern bearing, and any anode attached to the propeller nut.
Your shopping list may include:
- A split shaft collar: if fitted, measure the shaft diameter with callipers on clean metal. The bore must match the shaft exactly; boat length is no guide.
- A propeller-nut anode: match the nut shape, fixing method and retaining screw or thread. Shaft diameter alone does not identify it.
- Propeller-specific anodes: folding and feathering propellers from makers such as Volvo Penta, Flexofold, Max-Prop and Gori use different arrangements. Identify the maker, model and hub size.
Do not assume a collar replaces the propeller manufacturer's anode. Add one only where there is enough clearance and the installation permits it. Keep the stern bearing's water passages clear and follow the installation's clearance requirements.
Inspect hull and bow-thruster anodes
Look for external hull anodes mounted on studs, often oval or bar-shaped. Record their dimensions, stud spacing and any casting number, then inspect the internal bonding wires and terminals. An external anode protects equipment through its electrical connection. A loose or broken bonding wire can leave even a substantial anode providing little protection.
If your HR46 has a bow thruster, identify it from the motor or gearbox plate. Depending on the make and model, its anode may sit on the gearbox, beside the propeller or at a propeller retaining nut. Some arrangements have more than one. Order using the thruster model and parts drawing; a similar-looking anode may have the wrong recess or fixing.
Check other immersed equipment added during refits, including a stern thruster or underwater metal fittings with dedicated anodes. Bronze seacocks do not automatically require individual anodes. Their protection depends on the boat's designed bonding arrangement.