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).
The failure of a new petrol pump system and comparative performance tests.
| Identifier | ExFiles\Box 82\1\ scan0162 | |
| Date | 2nd August 1933 | |
| X4553A To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} From G.W.H. Hotel de France. Chateauroux. Indre. I. B. IV. We have sent you the following telegram after fitting the new petrol pump and standard pipe lines on dashboard: COMPLETE FAILURE OF PETROL SYSTEM WITH NEW PUMP AND STANDARD PIPES STOP ENGINE FAILS AT HIGH SPEED STOP AFTER STOPPING REFUSES TO START TEMPERATURES OIL 114 WATER 96 AIR 26. We fitted the new pump as brought out, then setting it with a .064 packing washer to bring the diaphragm in the same relative position as the pump taken off. The pipe lines and petrol tap were fitted in their standard positions. Tests taken during the morning gave shortage of petrol, engine allmost stopping, but no actual failure. At noon the engine being stopped whilst filling up with petrol, refused to start after using the petrol in the float chambers. It took 10 min. to get the petrol to flow (stopped in main street) After noon when the air temperature had reached 26° (run from Boulogne to here air 30°C) the car was run at high speed. The engine started to miss very badly due to shortage of petrol, it also started to preignite very bad. Upon slowing down the engine stopped alltogether and refused to start. After disconnecting the pipes it took 15 mins. to get petrol through. Tests carried out again with the same result. We cannot run under these conditions, we are therefore reverting back to our scheme which so far has not failed. We have allready informed you that the pipe leading from the petrol tap to the filter is never full of petrol, consequently the length of pipe becomes extremely hot. The petrol in the filter (standard position) vapourizes, which goes up the delivery pipe more so when engine comes to rest. We have since tested the delivery of the two pumps and from what we were informed both pumps are considerably down in effeciency. W. Bell stated that an effecient pump delivered 150 pts per Hr. at a pump speed of 2000; engine revs 4000. We give below the delivery of the two pumps: PUMP FITTED AT DERBY 4000 engine revs ( 37 4/5 sec for 1 pt ( or 95 pts per Hr. ( 38 " " 1 pt ( ( 38 " " 1 pt ( 2000 engine revs ( 37 sec for 1 pt ( or 97.2 pts per Hr. ( 37 " " 1 pt ( ( 37 " " 1 pt ( ( 37 " " 1 pt ( | ||