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).
Gearbox issues, including gear wear, noise, and engagement problems, with proposed modifications.
| Identifier | ExFiles\Box 15\5\ Scan382 | |
| Date | 7th March 1934 | |
| -2- Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}2/KW.7.3.34. We also noticed that the thrust plate that is used when engaging 1st gear or coming out of 2nd gear was distorted and worn. Edy. has given us a modification to overcome this. The gearbox is at present fitted with the strengthened 1st speed pinion. Both this gear and reverse are noisier than we could tolerate although they are ground gears. It appears from our tests that the 2nd speed teeth are easier to damage than those of top and 3rd speeds. In order to legislate for damage by unskillful use of the clutch pedal we consider that this part needs modification. The next trouble encountered was that it suddenly became impossible to engage either 1st or 2nd speed. This we found due to the 1st speed pinion seizing in the synchromesh sleeve which it helps to guide. The drawing clearance here is .006" and this we have increased to .013". The first speed teeth had considerably picked up in such a way as to increase the diameter of the pinion. To find out whether the tooth loading is too high on 1st gear we will run the first part of the dynamometer test on Whitemore's oil and then change to engine oil. The present 40/50 box does not pick up if run in in this way. Hs{Lord Ernest Hives - Chair}/H.{Arthur M. Hanbury - Head Complaints} Grylls. | ||