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 condition of an S.U. Petrol Pump after a 50,300-mile test.
| Identifier | ExFiles\Box 149\3\ scan0063 | |
| Date | 15th May 1939 | |
| 12634 400T To By.{R.W. Bailey - Chief Engineer} c. to By/RD. c. to HPS{Horace Percy Smith - Experimental Factory Mgr}/RH.{R. Hollingworth} c. to Rm{William Robotham - Chief Engineer}/RC.{R. Childs} RM{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}1/JH.15.5.39. S.U. Petrol Pump off 8.R.V. after 50,300 miles. This pump is fitted with Cast Iron High Pressure Type magnet housings, Neoprene Diaphragms, Tufnol guide bush and water excluding sleeves. The general condition of the pump on examination was exceptionally good, the front unit not having been disturbed throughout the whole mileage. The rear unit was stripped and reassembled after the first 18,000 miles test with the same parts. There was no signs of fouling between the armature and the pot. Rollers. The rollers had worn .0005" all round with no local flats and were not indented on the sides. The increased depth in the roller race to allow for the compression of the diaphragm appears to have cured this trouble and stopped the wear on diaphragm and rollers and reduced the amount of dust formed inside the pump. Tufnol Guides. These had only polished the spindles of the armature and not produced any measureable wear or steps. The bush was slack in the front unit but still in position (these were mocked up by hand). Diaphragms. The diaphragms were not porous or worn. Contact points. The contact points in the front unit were clean on the surface with very little soot formed and are estimated to be about 50% worn. On the rear unit the positive point had picked up a small piece of Tungston off the negative point leaving a pit. This has never occurred on previous endurance running of these pumps and we are of the opinion that this is an isolated case caused by a faulty negative | ||