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).
Parts to be fitted and performance data to be recorded for a 15,000-mile vehicle test.
| Identifier | ExFiles\Box 6\6\ 06-page427 | |
| Date | 29th January 1938 | |
| To RM{William Robotham - Chief Engineer}/TMW. Chateauroux, 600 1208 also 600A Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}2/JH.29.1.38. 26.G.VI. In so far as the unit in the above car is concerned, there are several parts which should be fitted before the car actually starts its 15,000 miles test which have come over as spares. They would have been fitted here if time permitted and are as follows :- (1) Valve springs and grummets removed the new grummets which have 6 ft. of material in place of the usual 4 ft. to be fitted. (2) Spare 6 valve springs to be fitted. These are marked green and are to EB.3256 made in Swedish wire by R.R. (3) Increased diameter 5/16 push rods to be fitted. (4) Front rocker shaft pedestal with hexagon head location screw and lock plate to be fitted. (5) Valve tappet clearances to be set at .008 with hot engine, which is equivalent of .006 cold. For your particular test we would rather know they have a definite clearance hot than when cold. We would like you to keep a record of the valve grummet collapse that is measure the springs length in the valve closed position when the grummets are first fitted and each time the tappets are checked. We should also like to know at what engine speed the valves bounce if you can notice same from time to time. Our tests on the test bed indicates that the valves start bouncing at 4,300 r.p.m. to 4,400 r.p.m. Will you please take a record of the oil condition say at the start and every 1,000 miles and fit the spare AC when the oil indicates that it is becoming dirty again. | ||