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 petrol pump on vehicle B-23-AE, caused by worn brass distance pieces.
| Identifier | ExFiles\Box 149\4\ scan0159 | |
| Date | 5th January 1937 | |
| To Rm.{William Robotham - Chief Engineer} Z.1263 Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}13/JH.5.1.37. Report on the Failure of the Petrol Pump on B-23-AE. These pumps were fitted with G-3 diaphragms on 14.8.36. since when the car has done 8510 miles at the same time one of the magnet unit was replaced. Both sides of the pumps were not working, the lead to one unit being broken. This was mended and the one unit worked satisfactorily. The other unit was removed and a new one fitted. On examination of the faulty unit, the setting was found to be correct and the diaphragm showed no sign of shrinkage or porosity. The reason for the failure was that three of the Brass distance pieces locating the armature had worn, and allowed the armature to foul both the mouth of the magnet pot and the pole piece. On examination it was found that the pole piece was not in the centre of the magnet pot. This causes an uneven annular air gap with consequent heavy side thrust on the armature and wear on the brass distance pieces. I have taken this matter up with the S.U. Company and they have agreed to check the pole piece and magneto pot for concentricity. Previously this has not been checked after assembling the coil in the pot and they have relief on the tool with which these are pressed. Rm{William Robotham - Chief Engineer}/J.B.Dixon. | ||