1976 Evinrude 40HP outboards Service Manual, Page 17Get this manual
SUBMERGED MOTORS If motor is lost overboard while running, it should always be disassembled before any attempt is made to start itOften internal parts are sprung and running under these conditions can result in permanent damage
A motor lost overboard in salt water should always be disassembled and cleaned before starting is attemptedSome materials used in modern engines are subject to very rapid corrosion in the presence of salt water and should be inspected to determine if replacements are requiredA motor lost overboard in fresh water can usually be safely started if recovered within twelve hours providing no sand or silt is presentRemove the spark plugs, the carburetor orifice screw, and drain all fuel lines and tankCrank the engine with starter rope until all water present has been expelledSquirt outboard lubricant into spark plug holesReassemble and startIf sand has entered the engineno attempt at starting should be madeDisassemble and clean the powerheadIf it is impossible to have the engine serviced immediately after it has been retrieved after extended submersion, it is advisable to submerge the powerhead in clean fresh water to prevent oxidation until it can be taken apart