6 - M
AINTENANCE
52
90-8M0077672 JUNE 2013
C
ORROSION
AND
C
ORROSION
P
ROTECTION
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 Quicksilver booklet,
Everything You Need to Know
About Marine Corrosion
for more corrosion information.
NOTICE
Using magnesium anodes in salt water causes an electrochemical
reaction on the metal surface of the drive, resulting in corrosion
damage from the paint blistering and peeling off the drive. Use
magnesium anodes in fresh water only.
IMPORTANT: Mercury Marine recommends installing an
Anti‑Corrosion Kit. If the boat is equipped with stainless steel after
planes, a large anode should be installed on each to handle the
increased galvanic corrosion potential.
Replace passive anodes if eroded 50% or more, or if the anode is
loose.
Mercury Marine recommends using anodes sold through Mercury
Precision Parts only. Some other manufacturers of aluminum
anodes use alloys that are insufficiently pure to adequately protect
critical drive components for the duration of the anodes' expected
life.
a -
Passive anode (trim pin)
b -
Passive anode (gear case)
c -
Active anode
In addition to the corrosion protection devices, follow these steps to
inhibit corrosion:
1.
Painting Boat Hull or Boat Transom
a. If anti‑fouling protection is required for boat hull or boat
transom, copper or tin base paints can be used unless
otherwise prohibited by law.
b
c
45811
a