LOW-PRICED OILS

Stratford Evening Post, Volume II, Issue 23, 19 August 1932, Page 7

LOW-PRICED OILS

ARE THEY GOOD LUBRICANTS If two products will do a job of work equally well, then the cheaper of the two is the better proposition, but, before a decision can be reached, consideration of the work on hand must be given. What are the main tasks of a lubricating oil in Ihe power unit of a motor.car? First, it must provide an oily film which will attach itself to the metal parts to prevent wear. This film should resist being removed \unrier conditions of high temperature, speed and load. The oil should (low freely at all operating! tempera'.ures, even on -a frosty winter morning, yet should not thin out excessively with increase in temperature—but, it must be tho correct, grade for the jo!). Oils tor automotive use should be well refined and free from acids, moisture, resins, wax and asphalts, or other impurities which may separate out or cause corrosion. Let us talk these main tasks over. .Any two metal surfaces, working together, must wear if they come lute contact, but they can be separated by a. film of lubricating oil pre. venting contact, provided the oil lias tile property of oiliness. Some oils have more of this property than others, and the more "oily" the oil, the better will it be able to penetrate between the surfaces, cling to them, and protect them from wear. Oilmenis the all-important factor in automotive lubricants.

What is the property of "oiliness,'' and what gives it? Frankly, we don't quite know. We know that oiliness, or lubricity, is a property possessed by some oils which enables it to reduce friction, and therefore reduces wear. We know that this property is inherent in certain types of crude oil to a greater extent than in others, and that careless refining can easily destroy this property. An oil possessing high "oiliness" is therefore one which is manufactured from carefully selected crude oils, by highly skilled refiners. These oil; cannot be produced cheaply. Distribution of oil within the en gine is an important factor. The lubri. eating system is - designed to give effective distribution, the oil is not too thick. An oil which will not flow freely at the temperature pre. vailing when starting, will not give elective circulation,, anc'J the surfaces are starved of oil until such times as the oil is sufficiently warm to circulate. A lot of wear can take place before this happens, and, in point of fact ; nearly half the total wear in an engine takes place wheii starting up from cold. That's all right! Put in a lighter bodied oil-but wait a minute. Oils all thin out with heal, but some thin cut to a much greater extent than others, and a poor quality oil which is sufficiently fluid to flow at starting temperature may be much too thin at working temperatures, and wear takes place. A good quality oil should not thin out excessively with heat, and will therefore be sufficiently fluid at low temperatures to give disfribu. tion and yet have sufficient body at working temperatures to give circula tion. In other words, high qualify lubricating oil resists change in body with change in temperature. What gives; <iih toil resistance W heaf changes? Again, the choice of crude oil, and the method of manu. t'acture'. Crude oils vary Widely! in composition and character. Sony crudes naturally endow a lubricating oil with the quality of resistance P heat, whereas others can only yield oils which thin out. excessively. Effi cieut refining methods are essential for treatment of oils to remove harm. I'nl or undesirable substances, yet they preserve or fester the desirable features. The result of efficient refinding of a well chosen crude oil is a high qualify lubricating oil. It cannot be produced cheaply.