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).
Internal document detailing the testing and recommendation of various lubricating oils, including castor-based and mineral oils.
| Identifier | WestWitteringFiles\T\2January1929-June1929\ Scan188 | |
| Date | 19th April 1929 guessed | |
| contd :- -2- To accomplish this it is essential that the oil be as thick as possible, consistent with other qualities, as otherwise the heat of the engine and warm weather will be responsible for high local rates of flow, which will seriously interfere with the correct distribution of oil. Our laboratory experiments indicate that for this purpose an oil with a castor base is preferable to either a straight or compound mineral oil. Castor oil maintains its mobility down to a very low temperature, and we find that Castrol 'R' is fluid at 13°F.{Mr Friese} This oil is also on Bijurs recommended list and heads the cold pour test with a working use down to -10°F.{Mr Friese} Our 10,000 miles car is being run using this oil for chassis lubrication and up to the present we have had no signs of any detriment accruing from it. It has an additional advantage in being a very clear oil, obtainable in quart tins. We should have liked to have been able to recommend Motorine 'C' or Amber A.{Mr Adams} since we already use these on the car, but the former is too thin for summer use and the latter congeals at 32°F.{Mr Friese} We believe, however, we shall be able to recommend in addition to Castrol R.{Sir Henry Royce}, Prices Motorine R.{Sir Henry Royce} which is of precisely similar constituents. In this manner we shall be recommending two proprietary brands, whose companies are already patronised by us and recommended to our clients for engine and gear oils. If a customer is going to lay up his car for a considerable time, it may be necessary to inform him that he must replace the Castrol oil in the contd :- | ||