1997+ Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-826148R2, Page 17Get this manual
Gear Case Lubrication When adding or changing ge ar case lubricant, visually check for the presence of water in the lubricantIf water is present, it may have settled to the bottom and will drain out prior to the lubricant, or it may be mixed with the lubricant, giving it milky colored appe aranceIf water is noticed, have the ge ar case checked by your de alerWater in the lubricant may result in premature be aring failure or, in fre zing temperatures, will turn to ice and damage the ge ar caseWhenever you remove the filldrain plug, examine the magnetic end for metal particlesA small amount of metal filings or fine metal particles indicates normal ge ar we arAn excessive amount of metal filings or larger particles (chips) may indicate abnormal ge ar we ar and should be checked by an authoriz ed de aler
WARNING
If gear housing is installed on outboard, to avoid accidental starting, disconnect (and isolate) spark plug leads from spark plugs before working near the propeller
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