Regal 2000 ES Owner's Manual page 274

Cosmetic Care & Maintenance
Zinc Anodes
Sacrificial zinc anodes are located on the stern drive/outboard
housing, trim cylinders and/or propsha to protect so er metals
exposed to the water. Electrolysis attacks the least noble metals rst.
Because zinc is a less noble metal, it will decompose before other
metals. Check these zinc anodes periodically and have them replaced
when they are 30% consumed. Notwithstanding, zinc is the most
popular metal used to protect parts that are exposed to saltwater,
freshwater or brackish water.
SACRIFICIAL ANODE
Zinc anodes in brackish or salt water need to be checked more
frequently. If the anodes seem to be requiring frequent replacement
there may be a boat leaking DC current into the water taxing the
anodes. is is especially possible around a marina environment.
Contact a marine professional who can measure the galvanic activity
with a special electrode and electric VOA meter. Refer to the engine
manufacturer's manual for anode location and detailed information.
Stern drive or related parts damage due to galvanic or stray current
corrosion is not covered under the Regal limited warranty.
VOLVO SHOWN
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