Attaching sacrificial anodes to boats with steel hulls

Key instructions

  • The anode should be positioned on the outside of the hull, below the waterline under the turn of the bilge.
  • The anode should not be positioned in front of or in line with echo-sounding transducers or log impellers.
  • When fitting and replacing bolt-on anodes, always ensure that the serrated fan disc washers are replaced.
  • The surface of the sacrificial anode should not be painted.

Other information

  • To provide the best protection for the stern gear, the shaft should be fitted with an electro-eliminator brush and earthed to the hull.
  • The gearbox should be bonded to the hull using 4mm² multi-stranded cable and any flexible couplings in the shaft should be bridged with a copper strap or cable.

The copper graphite brushes have a lifespan of at least 2,000 hours under normal conditions. The electro eliminators will also stop interference to electronic equipment caused by the rotating propeller shaft.