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 performance issues, specifically soot deposits, ignition problems at slow speeds, and potential valve clearance issues.
| Identifier | ExFiles\Box 34\3\ Scan009 | |
| Date | 10th September 1920 | |
| Contd. -3- RB{R. Bowen}/G10.9.20. of very slight deposits of soot spoiling the ignition, and especially affecting it at slow speeds. X.3763. I have just been over 1.EX engine and find that it appears in excellent condition, except for some reason or other which I have not yet determined, there is a distinct revolution variation in the exhaust at very slow speeds, especially noticeable on the battery ignition, when this is retarded. I am going to see if there is sufficient clearance in all the valves. I do not think it is a question of the disposal of the exhaust, but either a question of variation in the time of ignition or in the operation of the valves, probably owing to certain of the valves having something less than the standard clearance in the tappets. R.{Sir Henry Royce} | ||