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).
Service complaint memo about the failure of connecting rods, discussing weight variations and proposing stamping weights on future parts.
| Identifier | ExFiles\Box 132\2\ scan0237 | |
| Date | 19th May 1937 | |
| Hs.{Lord Ernest Hives - Chair} from Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} Rm.{William Robotham - Chief Engineer} RHC.{R. H. Coverley - Production Engineer} E.{Mr Elliott - Chief Engineer} By.{R.W. Bailey - Chief Engineer} Hd.{Mr Hayward/Mr Huddy} [Handwritten: 1119 also 1113] Rm{William Robotham - Chief Engineer}/GWH{George W. Hancock - Head Chateauroux}9/R.19.5.37. SERVICE COMPLAINTS. FAILURE OF CONNECTING RODS P.III, 25/30 & BENTLEYS. It has been the practice when a rod has failed to replace all rods irrespective of their condition, due to the risk of upsetting the balance of the engine. This is an expensive item, and cannot be avoided on the 3½-litre Bentley, owing to the instructions that Hall's metal must be fitted on all replacements. Also, under the existing conditions it would not be advisable to fit one rod, as the production of rods vary in weight to the extent of 1 oz. Bentley & 25/30 1 lb 7¾ ozs. to 1 lb 8¾ ozs. P.III - Plain rod - 1 lb 12¼ ozs. to 1 lb 11½ ozs. Fork rod - 3 lbs - to 3 lbs ¼ oz. It is the practice in the Works to pick out 6 rods of equal weight for each engine, a ¼ oz. being the limit of out-of-balance. No markings or records are kept of the varying weights of rods fitted. At the present, therefore, it is not advisable for depots to replace one rod on 4¼ Bentleys. To make this possible on all future cars, the weight of the rod complete could be stamped on the rod. The Depots then would give piece number and weight for a replacement. The D.O. would have to put these instructions on the drawing for the Works' information. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} | ||