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).
Summary report on various engine issues and modifications for different car models over a six-month period.
| Identifier | ExFiles\Box 47\3\ Scan256 | |
| Date | 30th September 1931 guessed | |
| -10- 20 HP. 25 HP. PH.I. PH.II. TOTAL. GRAND TOTAL. REMARKS. ENGINE - SLIPPER & SPRING DRIVES. September Quarter. C.C. 12 6 5 13 } 36 } 38 Early 20 HP. and Ph.I. These can be W.P. - - 2 - } 2 cured by fitting cotton duck washers in place of Bakelite. Previous " C.C. 20 2 5 15 } 42 } 43 20/25 HP. We do not have much trouble W.P. 1 - - - } 1 on these cars. Ph.II Latest type low inertia drive Six months. 33 8 12 28 81 81 with "Window" type pressure plates cures this trouble. See Depot Sheet Hd.{Mr Hayward/Mr Huddy}190. ENGINE - DYNAMO DRIVE RATTLES. September Quarter. C.C. 3 - - - } 3 } 4 This has always been a trouble on 20 W.P. - 1 - - } 1 HP. cars. No modification available. Previous " C.C. 2 - - - } 3 } 4 W.P. - 1 - - } 1 Six months. 5 3 - - 8 8 ENGINE - FAN PULLEYS. September Quarter. C.C. - - 7 9 } 16 } 76 Trouble definitely overcome by fitting W.P. - - 29 31 } 60 bolts instead of rivets. This is being done on all new cars, and on Previous " C.C. - - 6 14 } 20 } 54 existing cars when necessary. W.P. - - 27 7 } 34 Depot Sheet Hd.{Mr Hayward/Mr Huddy}210. Six months. - - 69 61 130 130 ENGINE - OIL PUMP NOISY. September Quarter. C.C. - 2 2 2 } 6 } 9 Depot Sheet Hd.{Mr Hayward/Mr Huddy}206 deals with the W.P. - 2 1 - } 3 fitting of an oil reservoir to the oil pump on Ph.II cars and is a definite Previous " C.C. - 2 3 1 } 6 } 7 improvement. W.P. 1 - - - } 1 Six months. 1 4 6 5 16 16 | ||