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).
Solutions for difficulties with mechanically operated petrol pumps.
| Identifier | ExFiles\Box 27a\2\ Scan135 | |
| Date | 31th March 1933 | |
| Rm{William Robotham - Chief Engineer}/Steatman To Hs.{Lord Ernest Hives - Chair} from E.{Mr Elliott - Chief Engineer} E.5/HP.31.3.33. x26^77 re Petrol Pumps Mechanically Operated. To deal with the difficulties which arise in connection with the use of a mechanically driven petrol pump such as we have instructed for Bensport, we have put forward certain proposals but none yet so far suggested deal adequately with the difficulties encountered in starting an engine with empty float chamber and pipe line or picking up after running out on the reserve. The scheme we put forward, shown on Lec.3110, using a reservoir and two-way cock coupled to the main and reserve petrol tap, did evacuate the reserve pipe as intended, but when put back on to the main pipe would not then evacuate the main. It would appear that this defect could be overcome by making the stand pipe and the reservoir of equal capacity, but even so this scheme does nothing to get a sticky engine going on a cold morning. We have also put forward the proposal to use foot valves in the petrol tank but we realise at the same time the extreme inaccessibility of such a feature and also that such a device only goes part of the way towards helping to overcome the difficulties we have in mind. We have suggested coupling up the starter carburetter with a lead of its own direct to the petrol tank and an experiment has been made showing that this picks up fuel very rapidly. It now occurs to us that instead of supplying a separate lead for the starter carburetter we could couple it up to the petrol pump at a point as close to the delivery valve as possible, the idea being to evacuate the air in the main fuel line and in the pump itself, and draw petrol as far as the delivery valve to the float chamber connection by means of the induction pipe vacuum. It was first thought that the connection should be made between the pump inlet valve and the tank, but there appears to be no reason why it should not be taken further along the system to include the pump as well in its operation. It would be necessary to incorporate in the starter carburetter control a cock shutting off the petrol when the starter carburetter was not in use. There appears to be | ||