OIL FALLACIES

Evening Post, Volume CVII, Issue 22, 26 January 1929, Page 25

OIL FALLACIES

BEWARE OF DOING} HARM

Some motorists have boon given the mistaken idea that when, tho moving parts are worn, a heavier grade oil should be used. This, however, is entirely wrong. As can be readily understood, oil cannot take the place of worn metal. If an engine wears so quickly that every few thousand miles it seems to need a heavier and still heavier oil, it looks as if tho oil were wrong in the first place and failed to protect the bearing surfaces. Even if a heavier grade than ono originally suitable could seal worn piston rings in a worn cyclinder, it might not bo readily circulated by the lubricating system employed, or along the oilways at a proper rate to supply correct lubrication to all parts of the engine, especially with a cold engine. If the engine were a naturally coolrunning one, the oil would "stew" on tho piston heads, causing carbon deposits and fouling of the combustion chamber; and there would bo other defects. The correct grade for all conditions 'is that recommended (and proved) by tho engineers. When an engine becomes badly worn, it should nave Hew bearings not new oil. No *a* mmld attempt to rectify, » lestk j»J

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Another fallacy is the idea that one class of. oil. will do for one class of vehicle; for instance, that a "heavy" oil will satisfy the needs of all motortrucks; an "extra heavy" all motor, cycles. To realise the fallaciousness of this one has but to carry the idea a little further, and say that one oil would successfully lubricate every unit, whether truck, car, cycle, or aeroplane. The design and conditions of operation of the various motor-truck engines vary, just as trucks uses do, from light to heavy loads, slow to high speeds. Therefore each of these designs lias to be studied, so that their individual needs may be catered for. And so it is with cycles, cars, or aeroplanes.