Regal 3300 Owner's Manual page 243

7. If marina moored, contact appropriate personnel if signs of galvanic
corrosion appear on your drive system. Ask them to check for stray
electrical current which may be originating from a nearby vessel's faulty
DC wiring or from a marina pier, piling or dock carrying leaking marina
ground wiring such as a dockside cord partially submerged.
Refer to the propulsion unit manual for additional information.
GALVANIC/STRAY CURRENT CORROSION
Cause/Observed Condition
Sacrificial anodes consumed
Sacrificial anodes not grounded
to drive
Loss of continuity between
underwater parts & ground
Nearby vessel with stray current
Paint on drive heavily worn,
exposing more metal
Sacrificial anodes painted
Drive tilted/anodes out of
water
Power trim cylinders only cor-
roded
Corrosion in area of exhaust
outlets
Corrosion occuring after vessel
is removed from saltwater
Stainless steel parts corroding
Underwater drive parts corrod-
ed, sacrificial anodes OK
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Cosmetic Care & Maintenance
Corrective Action
Replace anodes when 30%
consumed
Remove anodes, clean contact
surface, reinstall, check for
continuity
Provide good ground connec-
tions
Contact appropriate personnel
Remove your vessel from water
Prime and repaint or install ad-
ditional anodes
Remove paint or replace anodes
Leave drive down, install addi-
tional anodes below water
Provide a good ground to drive,
all parts must be grounded
Remove deposits
Wash exterior and flush interior
with freshwater
Clean parts, remove foreign
material, ensure continuity
Oxide film on anode (fresh wa-
ter only) Replace anode
Poor grd. Remove/scrape anode
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