Show occasional change of oil saves effice efficiency ency an engine to operate efficiently must have an occasional change of oil if its lubricating value Is diminished there is undue wear of 0 all engine parts which may lead to serious damage oil becomes practically worthless if an excessive amount of gasoline aso lias has become mixed with the lubricant so as to make it very thin or if witter water has gotten into it and caused it to emulsify or to contain free add also if dust metal particles pieces of carbon or other liard hard and abrasive material have polluted the oil in considerable quantities its further use will cause very rapid wear of engine parts |