Piston-cylinder crevice volume goes in-tough with fuel combustion products during the peak pressure time such as (i) at the end of compression stroke, and (ii) at the starting of the expansion stroke. If the fuel contains water molecule, later it converted to steam in the combustion chamber because of fuel heating. This steam-mixed fuel will increase excessive pressure in the cylinder, and consequently, water steam will be mixed up with lubricant at the crevice volume area, means mixing with lubricant, the later water-mixed lubricant will reduce flash (lubricant) temperature and quickly degrade lubricant functional properties. TQ

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