2006 Johnson SD 3.5 HP 2 Stroke Outboard Service Manual, PN 5006562, Page 42Get this manual
MAINTENANCE COOLING SYSTEM
COOLING SYSTEM
Check 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; all external water hoses and fittings
Shut OFF the outboardLeave the outboard in VERTICAL (DOWN) position long enough for the water to drain from the powerhead completely
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 passagesTYPICAL DR6434
Remove outboard from tank and install propeller&
WARNING
Water Intake Screens
Inspect condition of water intake screensClean or replace as needed