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).
Cause of a pump failure on chassis 3.CM.107, attributing it to rubber caps used with paraffin.
| Identifier | ExFiles\Box 96\1\ scan0332 | |
| Date | 7th July 1938 | |
| 1263 W/N. Br.{T. E. Bellringer - Repair Manager} from Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}1/R.7.7.38. Pump off Chassis 3.CM.107. Replying to Br2/LS.6.7.38., the cause of failure of this pump was put in a nutshell in the last sentence of the second paragraph of Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}7/JH.14.6.38. We have nothing to add to this statement. The 4th paragraph of this memo shows that the trouble is not likely to occur again. We do not agree we ever suggested that the paraffin used in the test rig could have been the cause of the trouble as implied in the 4th paragraph of your memo. The valves apparently never left their seats while the pump was on your rig. The paraffin on the Works' rig, with the rubber caps, caused the trouble. The circumstances which caused this failure were unique because the pump happened to arrive just before your test rig was in operation, otherwise it would have been discovered before being fitted to a chassis. It was also one of the few pumps fitted with the rubber caps, the use of which has now been discontinued. We have proved that it is only the rubber caps in conjunction with the paraffin which can cause this sticking, and we have never had another case since we reverted to brass. Rm.{William Robotham - Chief Engineer} | ||