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).
Engine oil consumption tests with various pistons and inserts, and a list of faults with the electrical equipment.
| Identifier | ExFiles\Box 111\3\ scan0083 | |
| Date | 27th April 1939 | |
| -3- Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}2/MH.{M. Huckerby}27.4.39. POWER - Cont'd.{John DeLooze - Company Secretary} Item (2) has been corrected during the strip of the engine prior to being fitted in 3.B.50 chassis. OIL CONSUMPTION ETC. With the combination of Wraith type split skirt pistons (fitted to reduce bore wear) and the block, i.e. Nos.1 and 2 std. bores, Nos. 3 and 4 Hichrome and Nos. 5 and 6 Brivadium short inserts, also fitted to compare for bear wear, the oil consumption figure over the first 1 hour run was very high, 7 pts/hr. A second run brought the figure down to 5 pts/hr. and a third to 3 pts/hr. In view, therefore, of this rate of improvement the engine was passed off at this figure. With normal standard bores and the latest close clearance Aerolite pistons, the average consumption starts at 2 pts/hr. and eventually settles down to 1 pt/hr. or even less. The figures of 7 pts/hr., 5 pts/hr. and 3 pts/hr. are far from satisfactory as a production job owing to the running time necessary to bring it down to a reasonable figure. Unless "lapping in of rings" is resorted to there is a lot of work necessary to find a piston and ring combination that in conjunction with short inserts will give a good quick consumption figure. ELECTRICAL EQUIPMENT. The complaints we have on the electrical system including the latest R.R. distributor can be listed as follows:- (1) The oiler is in such a position that oil runs away from the parts it is intended to feed instead of to them. (2) The distributor cover marked for anti-clockwise instead of clockwise direction of rotation. (3) Both the rotor arm and the felt cam lubricator came loose on their rivets. (4) The distributor driving dog and the riveting of the distributor drive should have a predetermined relationship with the rotor and timing, so that the distributor head is on all engines in a constant position. | ||