2003 Johnson ST 6/8 HP 4 Stroke Outboards Service Manual, PN 5005471, Page 46Get this manual
MAINTENANCE COOLING SYSTEM The multimeter should indicate little or no resistance
COOLING SYSTEM
Verify the condition of cooling system components regularlyThe outboard cooling system consists of: water intake screens; overboard water pressure indicator; water pump; all internal water passages; thermostat; all external water hoses and fittings;
IMPORTANT: Anodes that are not eroding may
indicate that the anodes are not properly groundedAnodes and the mounting screws must be clean and tight for effective corrosion protection For best anode performance: Replace all anodes that have eroded or disintegrated to two-thirds of their original size Do not paint or apply protective coatings to anodes or anode fasteners Avoid using metal-based antifouling paint on the boat or outboard
Flushing
Flush the outboard with fresh water following each use in brackish, salt, or polluted water to minimize the accumulation of scale and silt deposits in cooling system passages
Metallic Component Protection
Protect metal components on outboards from corrosionUse the following products to minimize corrosion Anti-Corrosion Spray provides heavy, waxy coating to protect components "6 in 1" Multi-Purpose Lubricant provides thin film of anti-corrosion protection