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).
Test results and analysis of standard pump performance with shortened stroke and G.3 diaphragms.
| Identifier | ExFiles\Box 149\4\ scan0018 | |
| Date | 2nd October 1936 | |
| -5- Hs{Lord Ernest Hives - Chair}/JBD.{John B. Dixon - Fuel Systems}14/KW.2.10.36. Standard Pump, Shortened Stroke. Temp: Pump & Air Suction Head Delivery Time °C. Inches Petrol Secs. 35 14 56 45 13 58.1/5 55 12 60.2/5 62 12 62 75 11 64.1/5 85 11 65 Standard Pump. G.3 Diaphragms. Temp: Pump & Air Suction Head Delivery Time °C. Inches Petrol Secs. 35 14 53 45 16 51 55 17 51.2/5 62 17 50.4/5 72 17 51.3/5 85 17 52.3/5 This showed us that the increase in temperature did not have as great an effect on the pump's ability to deal with vapour as the S.U. Co. led us to believe. In the course of the above tests it was found that water in the petrol had a serious effect on the G.1 diaphragm material (which is slightly acid), dissolving it and causing corrosion of the pump body and blocking up the valves. It was also found that at the temperatures used, namely, 45-50°C., for the petrol, the material became dehydrated and shrunk, so that after cooling and becoming stiff, the pump failed to work. A comparative test between the G.1 and G.3 materials resulted in the failure of the G.1 to start up in the morning after 3 days' running with petrol at 45-50°C. When taken down the material was stiff and loose in the armature spindle owing to shrinkage. This has occurred in service and has always previously been attributed to bad fitting in the first place. | ||