Potential cause of loose split pins being the introduction of the synchro-mesh gearbox.
| Identifier | ExFiles\Box 107\1\ scan0167 | |
| Date | 23th February 1933 | |
| x7960 To Wor. {Arthur Wormald - General Works Manager} From Hs. {Lord Ernest Hives - Chair} Hs. {Lord Ernest Hives - Chair} 4/MJ.23.2.33. Re: Chassis GAU-48 - Park Ward Trials Car. Replying to Wor. {Arthur Wormald - General Works Manager} 1/GR. {George Ratcliffe} 21.2.33. The reason why 142 cars are quoted as being doubtful is because it has been assumed by By. {R.W. Bailey - Chief Engineer} that it is the introduction of the synchro-mesh gearbox which has been responsible for high engine revs, which in turn is more likely to wear loose split pins. It means all 25 HP. cars have had the loose split pins before synchro mesh gear-box and 142 cars with synchro-mesh gearboxes. The reason for the change in split pin came about due to the failure on the aero engines caused by loose split pins, and it was decided then to go over all our engines and tighten up the fit of the pins. We are not convinced that the synchro mesh gearbox is a decided factor in this failure. It is very much open to question. The car which was examined was an experimental car which has been running for two years, in which the split pins were the original slack fit. The engine of this car has been raced at high speeds including tests in France very much more than we should expect a customer's car to run, and there was no sign of deterioration on the split pins. We understand E.W.T. has a list of the 142 cars which BY. {R.W. Bailey - Chief Engineer} raises a doubt on, and no doubt he will be able to tell them the numbers of their Trials cars which come under this list. Hs {Lord Ernest Hives - Chair} , | ||
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).