From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Bentley cylinder bore wear and oil consumption tests for car B.23.AE.
Identifier | ExFiles\Box 132\4\ scan0088 | |
Date | 28th September 1937 | |
BENTLEY CYLINDER BORE WEAR AND OIL CONSUMPTION B.23.AE. The special features on this car are as follows:- (1) Low Brinell cylinder block produced without chills in the bore, but otherwise to normal specification for cylinder iron, 212.A., Brinell = 236. (2) Venturi type crankcase breather to Rm.{William Robotham - Chief Engineer}398. (3) Higher pressure compression rings having wall pressure of 18 lbs/sq.in. (4) High pressure scraper rings 32 lbs/sq.in. wall pressure, now standardised and on Production. (5) Pistons with increased taper on skirt, now standardised and on Production. (6) Large capacity oil pump. (7) Crankshaft with one hole in crankpin. Oil Consumption The cylinder block, pistons and rings were fitted to this unit whilst in car so that they had no real running in as on bed, the engine being given approximately 4 hours light running in chassis. The first consumption test gave 830 miles/gall. at an average speed of 49 M.P.H. At end of 6000 miles the oil consumption at an average speed of 53 M.P.H. is approximately 1500 miles/gall. After approx. 2500 miles of running since fitting of pistons etc. comparative tests were made with small and large capacity oil pumps, these gave the following figures:- Large pump - 1500 miles/gall. Small pump - 1550 " Both these tests were carried out at average speeds over the same run of 53-54 m.p.h. continued | ||