National Geographic : 1915 Sep
What does your oil do? Does it lubricate correctly-save power protect your motor? Or does it just burn up? IF you have checked up the It results naturally in sheer oil - mileage which different oils waste. But it results, too, in yield on your car, you have other more serious consequences. probably found that One is excess carbon some oils are con- deposit. sumed far more Where Of course too rich rapidly than others. oil a gas mixture is a -=wastes Why ? frequent cause of car | .. oil to h bon trouble. But the If an oil too heavy experienced motorist in body is used, it knows-or should will fail to reach all know-that an excess friction points. of lubricating oil in Often an oil is too ... thecombustioncham light in body for the motor's me- bers must result in unnecessary chanical conditions. Excessoil then carbon trouble. gets by the piston rings. Reaching To minimize carbon, your lubri the combustion chamber it burns. eating oil must be of the correct When oil consumes rapidly, body for the piston clearance of power-waste also occurs. The fuel your motor. charge escapes past the piston Correct body is no subject for rings on the compression stroke. guess work. Gasoline consumption mounts up. - A very large and rapidly grow Even with oils of correct body ing class of motorists have found a minute quantity of the oil works that their safest guide to correct past the piston rings and is body in lubricating oil is found burned up. in the lubricating Chart on the But with oils of incorrect body right. This Chart has for several this consumption becomes rapid. years been the standard guide II Illllull5lllllI lli nll IIIIIIIIIIIII IIIIIi niIIII1111111111111111111IIIIIIIIIIIIIIIIIIIIInilIII InIII1IIIIIIIIIIIIIIIIIIIIIIIIIIIi "Mention the Geographic-It identifies you."