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).
Modifications, trials, and rising complaints regarding S.U. petrol pumps.
| Identifier | ExFiles\Box 149\6\ scan0108 | |
| Date | 9th November 1937 | |
| 1263 By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems} c. Da.{Bernard Day - Chassis Design} Mx.{John H Maddocks - Chief Proving Officer} Rm{William Robotham - Chief Engineer}/JBD{John B. Dixon - Fuel Systems}/R/9.11.37. S.U. PETROL PUMPS. The petrol pumps which were made or returned for modification before July this year had no limit on the concentricity of the pole piece. Since then all new pumps have been centred to within .005" including those returned for repair or modification and stamped 'G5SC' which mark includes the oil silk insert in the diaphragms. We have end cutters to trial existing pumps and all the experimental cars have been so treated, and there have only been two cases of failure attributed to pieces of the metal shaving remaining in the pump after the operation. The use of the end cutter on the pole slightly more than halves the existing eccentricity and should reduce the side load by 4. One of these cutters was issued to the Paris Depot where, owing to Customs difficulty, they have been doing all their repairs. Of 15 pumps they have treated there have been no recurring failures. The cutters were not issued to Kingsbury or Cricklewood where pumps are sent back to the S.U. Works for modification, this has until now been carried out 'free of charge', and so long as the S.U. Company continue to do this, even in the case of G.5 pumps, which have already been back to them once for modification, we would incur unnecessary expense if we used the cutters at the Depots. If at some time they charge for this work we have the cutters available and could ascertain if the work could be done cheaper at the Depots. From analysis of the Bentley petrol pump complaints supplied by Kingsbury, the number of G.5 pump complaints has jumped very rapidly last month. The total complaints on this type diaphragm having risen from two in January to 37 during October, of this number 23 are due to leaky diaphragms, and 8 due to failure of one or both units. This rapid increase of the number of faults on the G.5 type has been accompanied by a falling off in the number of complaints on the older types of diaphragm as the number of this type has been replaced. | ||