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).
Examination report on the issues found with S.U. petrol pumps for a Phantom III vehicle.
| Identifier | ExFiles\Box 149\4\ scan0265 | |
| Date | 2nd May 1937 | |
| 1263. HOTEL DE FRANCE, CHATEAUROUX. Indre. France. Rm{William Robotham - Chief Engineer}/JBD{John B. Dixon - Fuel Systems}/3/JAB. 2nd May 1937. To. Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems} 35-EX. PHANTOM III. S.U. PETROL PUMPS. I examined the double unit, both sides of which had been reported as having shrunk diaphragms which were of the G.5 material with two layers of oil silk. Fitted 13.4.37 since when they had covered 7,660 miles, running alternately on Esso Ethyl and Azure alcohol. The toggle mechanisms were free and points in good condition and the setting of both sides correct. On further examination, both armatures had been fouling the centre pole piece in the magnet pot and also on the outside edge of the pot. In each case this was due to eccentricity of the pole piece in the magnet unit. This defect has been reported on previously and steps taken to prevent it happening on new pumps. This agrees with the symptoms as reported by IMW{Ivan M. Waller - Head of Chateauroux}, the fact that the pumps did not stick until hot, I attribute to the loss of power in the solenoid due to heat when the friction caused by fouling the pole piece would have more effect and hold the armature from coming right back and breaking the toggles. This will require investigation and confirmation. The Diaphragms. Both diaphragms were well bulged and flexible, and the material definitely had not shrunk. The two layers of oil silk were very wrinkled with more than adequate slack to allow for the diaphragm movement. The effect of the fuel was very evident on the G.5 material, the dressing had been partially disolved and deposited on the oil silk. The oiled silk had stuck to the G.5 material where the diaphragm is clamped together and on separating it for examination some of the dressing on the silk adhered to the G.5. The oiled silk showed no sign of failure either by fatigue or action of the fuel, and gave no indication that it was near the end of its life. To continue running, the pumps were built up and some of the worn distance pieces replaced. When tests were carried out yesterday, there was no trouble due to sticking either hot or cold. The delivery taken at the end of the flexible pipe was as follows :- All three pumps.... 240 pts. per hour Double pump....... 180 " " " Single pump....... 120 " " " B/Rm{William Robotham - Chief Engineer}/JD.{J. Draper - Frames} | ||