Extended oil life reduces damage to Engines during cold starting:
If all the parameters are kept within allowable limits, oil which has been used for 2000 hours is certainly better than oil used for 200 hours . It is an established fact that maximum damage to any engine occurs at the time of cold starting when all the parts have started movement ,but the lube oil has not reached there ,it will reach after a few seconds. After the engine is shut down, every drop of engine oil comes down to sump within a few hours, and when engine has been restarted cold again, many parts make movements in dry condition waiting for the lube oil to arrive there.
When the oil is new , it has both weak and strong molecules, the more the oil is used, the more these weaker molecules get oxidised. When the oil becomes very old, the proportion of strong molecules becomes almost 80% and more and the adhesive power of oil increases, the strength of oil film oil increases. Thats why when the oil is older more than normal drain out period, i.e.2000 hours old, it sticks to every nook and corner of the engine for more than 72 hours. So at the time of cold starting, oil is present everywhere and damage to engine is least .
Thats why 2000 hours old oil is better than 200 hours old oil. If you want to enhance the life of engine, extend the drain out period of engine oil to the extent of NO MORE CHANGE OF OIL, yes, but with some device you have to keep all the parameters of oil within allowable limits.
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