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).
Petrol system failures due to air ingress on 4¼ litre Bentley and 25/30 HP chassis, with proposed design solutions.
| Identifier | ExFiles\Box 149\1\ scan0234 | |
| Date | 23th May 1936 | |
| X1263 F.{Mr Friese} DODD. E.{Mr Elliott - Chief Engineer} c. Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer} We showed check over one or two pumps dry. Suspect real complaint is leak on suction side Rm{William Robotham - Chief Engineer} re 4¼ litre Bentley & 25/30 HP. Chassis Petrol System Failures We still continue to have one or two cases during our final tests of complete cars at coachbuilders, or whilst new cars are being delivered and demonstrated to customers, where an involuntary stop takes place owing to the engine running short of petrol. In all such cases the trouble appears to have been due to air getting into the petrol system, and the time taken for the petrol pump to get rid of the air is sufficiently long for the engine to run short of petrol and stop. It must be appreciated that the question of air in the system is probably aggravated by the conditions, i.e. after standing at the coachbuilders for some time without petrol in the system, and during these tests and demonstrations only about two or three gallons are put into the tank. It is a condition, however, which may happen in the customer's hands, and we must therefore be prepared to deal with these complaints. As discussed with you on the telephone, the point is one which we feel should receive your consideration as regards design:- (1) That all the petrol pumps should be checked and tested under dry conditions to be self-priming with a lift of at least 100% more than that required on the chassis. (2) The tank might be altered, or a well fixed, so that air is not drawn into the system when the petrol level in the tank is low. EP{G. Eric Platford - Chief Quality Engineer} EP{G. Eric Platford - Chief Quality Engineer} | ||