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).
Strength of rear engine mounting bolts and recommending a conversion to the Diamond engine mounting system for the 40/50 HP car, 58-GN.
| Identifier | ExFiles\Box 14\5\ Scan236 | |
| Date | 3rd September 1931 | |
| 7005 To Sg.{Arthur F. Sidgreaves - MD} From Hs.{Lord Ernest Hives - Chair} c. to R.{Sir Henry Royce} Wor.{Arthur Wormald - General Works Manager} c. to By.{R.W. Bailey - Chief Engineer} Hs.{Lord Ernest Hives - Chair}4/MJ.3.9.31. 40/50 HP. - 58-GN. Replying to Sg{Arthur F. Sidgreaves - MD}11/E2.9.31. The bolts you refer to for holding the rear/engine unit are amply strong. We have carried out a 100 hours bumping test with the engine mounted the same as 58-GN. Also, when we use Diamond engine mounting we still rely on these two 3/8" bolts you mention for holding the rear end of the engine. On any customers cars which have had the rear engine feet disconnected, we have taken the precaution to still leave these feet connected to the engine but just clear of the frame so that in the event of anything happening the engine could only drop a very small amount. The purpose of these feet is not so much anticipating failure of the bolts, we do not think there is any likelihood of this; the chief object is that they allow the gearbox to be dismantled without taking the engine unit out of the frame. 25-EX. car, which has had a good gruelling in France, has no more support than 58-GN. The recommendation is that now we have completed tests on the conversion scheme with the Diamond engine mounting, 58-GN. car should be altered to this. We think it would be a good thing to carry out because it would give you an idea how much it is going to cost to do this on customers cars. Hs.{Lord Ernest Hives - Chair} | ||