OIL AND STARTING.

Star (Christchurch), Volume LXVI, Issue 20632, 5 June 1935, Page 11

OIL AND STARTING.

Interesting Tests Show Results. Tests carried out recently by the University of Birmingham Electrical Engineering Department disclose important facts as regards starting a motor-car engine in the winter time. The tests were carried out on a sixcylinder engine of well-known make, at a temperature of 32 deg. F. (freezing point). It is accepted that 60 revolutions per minute is the approximate minimum speed at which the average four or sixcylinder engine will start under favourable circumstances. With heavier grades of oil this speed was difficult to obtain. With recognised winter .grades of oil—Mobiloil A and Mobiloil AF were used by the university—the engine crankshaft speeds were 134 and 103 respectively. These figures show the undoubted value of these oils from the point of view of starting, but they possess ah added advantage—more rapid circulation, and therefore quicker lubrication at low temperatures. There is still another advantage to be gained from the use of the correct winter grade of oil, which was demonstrated in some tests recently conducted in Sydney. A Heenan and Froude tester was used, by which apparatus horsepower delivered at the road wheels is accurately measured. These tests that with the lighter winter Mobiloil as much as 5 per cent more power was developed under normal winter operating conditions than with a summer grade of oil in the engine. Further power is gained at the rear wheels by correctly lubricating the gearbox, differential and other components for winter driving. Summed up, it has been scientifically proved both in England and in this part of the world, that the use of the correct grades of lubricants during the colder months (i.e., “ winterproofing ” ones car), gives easy starting, proper lUDrication protection of moving parts, and full power instead of a sluggish engine. g