Regal 3300 Owner's Manual page 242

CHAPTER 7
The vessel should be tested every couple of weeks to determine the
integrity of the anode protection system. If not installed, Volvo and
Mercury offer an optional corrosion protection system that utilizes
the anode/cathode theory to assist in offsetting galvanic corrosion.
Another way to test the system is to measure the hull potential. This
is accomplished by immersing a reference electrode, usually a silver/
silver chloride into the water about six inches behind the drive. With
leads attached to a digital multi-meter the hull potential is read on the
DC scale and compared to recommended specifications for the water
body type.
Tips To Aid In Maintaining Galvanic Integrity
1. Test the galvanic integrity of your vessel every 2 weeks. Raise the outdrive
and inspect anodes/parts for signs of galvanic corrosion, stray current
corrosion or loose fasteners. Contact your closest Regal dealer/certified marine
technician where signs of galvanic corrosion exist.
2. Never paint over anodes as they will become inoperative. Always
leave at least one inch between bottom paint and any underwater fitting
such as seacocks, swim platform stanchions and all drive and propulsion
related underwater parts.
3. Periodically remove vessel from water and clean/pressure wash all
outdrive, anode and hull bottom areas to remove growth.
4. Ensure vessel is using the correct anode metal for the body of water
that it is moored. See the engine/drive manufacturer information
packets for more information or contact an authorized dealer.
5. Ensure that the drive is completely "in" down to provide more
complete anode protection when vessel is moored.
6. Do not attempt to use magnesium anodes in saltwater. They will
provide overprotection.
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