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).
Recommendations for American owners on castor oil lubricants and an update on magneto issues and improvements.
| Identifier | WestWitteringFiles\G\June1921\ Scan16 | |
| Date | 1st June 1921 | |
| To R.R. of America Inc. -10- R10/CS/6/21 Contd. from R.{Sir Henry Royce} American owners should be encouraged to use a mixed lubricant largely composed of castor oil, which I then stated was specially suitable for their requirements, as they complained of cylinder wear largely due, I believe, to the petrol in cold weather washing the oil off the cylinder walls. The oil should contain roughly 80% to 90% castor oil, the rest being mineral, as stated in the memo in question. Mr. Hives recently confirms that inefficient lubricating oils is the cause of wear, i.e. bad quality of oil, and also good oil which has become dirty or diluted with kerosine from the gasoline. Remedy - use better oil as advised, and clean out sump more often. MAGNETOS. Regarding the magnetos, the only fault we have been able to so far find with the Watford is that the safety spark is rather short, which seems to be always the case on the smaller sizes of magneto of all makes. In certain conditions of compression in the cylinders, and wide spark gaps at the ignition plugs, this causes the safety spark gap to act instead of the spark passing at the plug points, and so misfiring occurs. On the European cars we are adopting the sleeve type of Watford in which the collecting ring from the armature can be larger by the thickness of the sleeve. This magneto, although of light and small size, has all the advantages of the bigger model, firing at equal and low speeds in any position of the advance, and so permitting the full retarding of the magneto ignition when running dead slow. (Contd.) | ||