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).
The performance and issues of the clutch and gearbox, including modifications with Cadillac gears.
| Identifier | ExFiles\Box 92\3\ scan0277 | |
| Date | 26th January 1937 | |
| ( 10 ) very small range of the pedal movement, so that care was always needed not to let the clutch in with a jerk. The thick shafts showed up any carelessness in this direction owing to the reduced resilience of the transmission, but at the same time they did overcome the transmission rattles. The reduced pedal pressure was much appreciated. The facings gave off a most penetrating and unpleasant smell with the slightest amount of slip. A total loss of clearance of 2.5" was recorded in 20,000 miles. This means that the clutch must be adjusted or checked once every 6,000 miles to ensure that the pedal does not come up to the boards. Under traffic test conditions, adjustment has been shown to be necessary every 2,000 miles. The clutch fingers rattled badly and became more audible as the pedal travel decreased or if the foot was rested on the clutch pedal. The rattles were worst at 60-70 m.p.h. but were also audible above and below this speed. The thrust bearing was noisy at the start but became quieter during the running. It was always noticeable with light pedal depression. Excess oil leaked from the tail bearing. The feed was therefore reduced from N° 3 to N° I bijur. Gearbox. Gearbox and actuating gear LOP.G.82818. N.S.4537 - N.S.4582-3 N.S.4567-4428-4764. 1st & 3rd Motion shafts LOP.G.83179 (Cadillac Gears) 2nd Motion Shaft LOP.83180 (Cadillac Gears) Reverse Gears LOP.83181 N.S.4414-4432-4392. Change Gear & Brake Mechanism LOP.G.83257 incorporating N.S.4929 increased travel of horizontal hand brake lever and increased leverage 84-I. The following scheme incorporated to HPS{Horace Percy Smith - Experimental Factory Mgr}/CP.20/BA. 26.1.37. Arrgt.Ex.25331 Special Ransome & Marles Bearing fitted at output end of 3rd Motion Shaft. At the start of the mileage, the gears were somewhat noisy due to fitting the Cadillac gears in a new box for further mileage. They became a good standard for quietness at the end of the mileage, as the gears bedded in. The synchromesh was lumpy in operation and rapid gear changes were not possible, but the gears could not be crashed. With the bedding in of the cones, the change steadily improved and was good after 10,000 miles, remaining good for the rest of the mileage. (contd) [Handwritten Text] Chandler Has the increased pedal travel been standardised Sheet issued 16-2-37 Completed 25/3 | ||