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).
Specification for the overhaul of the 9.B.V. B.V. No.4 unit in preparation for a 15,000-mile test.
| Identifier | ExFiles\Box 168\3\ img053 | |
| Date | 31th December 1936 | |
| 6119 Re - HPO; from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} S. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}1/MH.{M. Huckerby}31.12.36. 9.B.V. B.V. No.4 UNIT (15,000). It is proposed to overhaul the above unit in preparation for the 15,000 miles test of this car. Will you please dismantle and inspect and assemble to the following specification. (1) Existing crankcase if O.K. from crack test. (2) New set of shim-less R.R. whitemetal main bearings. This type now standard on 'C' series Wraith. (3) Crack test connecting rods and fit new bolts. New set of standard Wraith big ends to be fitted. (4) Inspect and measure crankshaft; it is anticipated that little wear will have taken place. (5) Raised crown Aerolite pistons P.452 to be fitted, which with .030 Klingerit gasket gives 6.6 : 1 compression ratio. (6) If no slack has developed in timing gears use existing original type of light inertia Attwater's camwheel. (7) Spring drive to be brought up to date to LOP.EB.4275. (8) Cylinders to LOP.EB.4317 which incorporates modified cored cylinder block and head EW.1922/3. (9) Valves and fittings to EB.4310, except following which should be included:- (a) Nos. 1 - 4 valves to have seal arrgt. ECD.1014 (Fig.1) " 5 - 8 " " " " " ECD.1014 (Fig.2) " 9 - 12 " " " " " ECD.1022 (b) Push rods to ECD.1096 which prevents the push rod coming out of the adjusting screw sphere in the event of valve sticking or spring failure. The above is outcome of failure on the first 15,000 miles on 8.B.V. | ||