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).
Letter detailing modifications to S.U. petrol pumps and arrangements for car shipment from France to Derby.
| Identifier | ExFiles\Box 82\1\ scan0231 | |
| Date | 28th August 1933 | |
| XU5513 Hotel de France. Chateauroux. Indre. To Hs.{Lord Ernest Hives - Chair} From G.W.H. 28.8.33 I. B. IV. We received your telegram this morning. Four men have left for Derby. Roberts and myself leave to-morrow. The car is leaving here to-day for Paris adressed to GENERAL Transport Co. They will then deal with it for shipment to Derby. We have placed in the rear of the car three axle tubes which have been taken off. The General Transport Co. delt with these so there should be no difficulty clearing same. We have made numerous tests with the S.U. petrol pumps and found some very interesting data. We found that the impulses of the pumps connected together by 5/16" pipes caused uneven operation of them. The fitting of a delivery pipe to each pump up to the junction of the carburettors gave an increase in petrol delivered and a steady flow. We then fitted an expansion chamber at the junction of the two delivery pipes approx. 1 foot from the pumps using one pipe line from the expansion chamber as previously. This gave us the same delivery as when using two seperate pipe lines. There was still a certain amount of hunting with the pumps. This was traced to using one wire for the two pumps, the pumps being bridged with the one wire. What happens, is, when one pump makes contact, the current consumed by the solenoid coil drops the voltage so that there is not sufficient to operate the other pump. This occurs intermittantly. By bringing two seperate leads this does not take place and we obtain a uniform working of the pumps. With these modifications we are obtaining a regular delivery of 133 pts. per Hr. - 16 pts. more than the engine petrol pump gave. The sketch shows how the system is now fitted and is entirely satisfactory. GWHancock. G.W.H. | ||