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).
Modifications and testing for Phantom III gearboxes due to issues with gears jumping out of mesh.
| Identifier | ExFiles\Box 94\2\ scan0006 | |
| Date | 8th June 1936 | |
| To RHC.{R. H. Coverley - Production Engineer} 7326 Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}33/KW.8.6.36. Phantom III Gearboxes. Owing to an epidemic of gears jumping out of mesh, we shall have to alter instructions we have sent you about gearbox specifications. The American method of driving on 6 adjacent teeth only has been successful on one box. We wish to try this again and send you Rm.{William Robotham - Chief Engineer}141 showing the full scheme for all speeds, in which the remaining teeth are present but undersize so as to do their share of the work during bad synchromesh changes. Will you please fit this scheme to Box 4HS{Lord Ernest Hives - Chair} retaining the Cadillac gears. We shall test this in 30-EX. No. 9HS.{Lord Ernest Hives - Chair} for 37-EX. We think this box should be modified before fitting in the chassis. Please fit N.Sch.4820. 36-EX. When this car is next in the shop, change gearbox 7HS{Lord Ernest Hives - Chair} for box No.33-EX, so that we can dynamometer the former or send it to G.W.H. as a replacement box for 32-EX which is giving trouble. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||