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).
Letter to G. Smith, Esq. discussing the effectiveness of by-pass oil filters and critiquing recent technical articles.
| Identifier | ExFiles\Box 90\2\ scan0095 | |
| Date | 4th October 1938 | |
| G.Smith, Esq. -2- 4th. October 1938. The By-pass filter on the other hand, is constantly dealing with a small flow of oil at low pressure and could abstract the dirt from this oil most effectively. The curious thing is that all the oil does go through a By-pass filter in a remarkably short space of time. As an example, if you put one on your car, in 60 to 80 miles' running, unless the oil was in very poor condition, it would be brought up to an amber colour. I attach particulars of a filter of this type which we have found to be most effective from our tests. By the way, some technical articles have been appearing in "The Autocar" recently in which some rather doubtful statements have been made. I must say that such articles must inevitably arouse a certain amount of antagonism in the minds of the technical staff of motor manufacturers. Generally speaking, most of your technical articles in the past have been very sound in spite of the fact that you do not cater for the Engineer. I do suggest that your present series is not up to your standard of the past. Yours sincerely, | ||