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).
List of modifications to be carried out on Unit No. 7 34 EX.
| Identifier | ExFiles\Box 114\4\ scan0028 | |
| Date | 2nd February 1937 | |
| 17 Derek HPS{Horace Percy Smith - Experimental Factory Mgr} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}19/M.2.2.37. No. 7 Unit 34 EX. Will you please carry out the following modifications on this unit. (1) 4 felts to be fitted in the valve end of each rocker. (2) Drill .015 hole in the annulus of each rocker bush. (3) If worn, replace existing tappets adjusting screws by new ones incorporating the oil grooves, likewise the bottom ball ends of the push rods. (4) Up to date gauze tappet and main oil filters to be fitted. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||