Corrosion Protection - MerCruiser 3.0 MPI Owner's Manual

Section 5 - Maintenance

Corrosion Protection

Washing the MerCathode assembly can damage components and lead to rapid
corrosion. Do not use any cleaning equipment such as brushes or high‑pressure washers
to clean the MerCathode assembly.
Whenever two or more dissimilar metals (like those found on the sterndrive) are submerged
in a conductive solution, such as saltwater, polluted water or water with a high mineral
content, a chemical reaction takes place causing electrical current to flow between metals.
The electrical current flow causes the metal that is most chemically active, or anodic, to
erode. This is known as galvanic corrosion and, if not controlled, it will in time cause the
need for replacement of power package components exposed to water. Refer to the Marine
Corrosion Protection Guide (90‑88181301).
Page 78
c
a
b
a - MerCathode reference electrode
b - Do not paint
NOTICE
c - Do not pressure wash
90-899883272 MARCH 2008
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