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).
On a new instrument board-operated primer for the 6.EX Car, detailing an issue and solution related to pressure in the fuel system.
| Identifier | ExFiles\Box 46\1\ Scan157 | |
| Date | 9th October 1920 | |
| X4138 Extract from Hs{Lord Ernest Hives - Chair}1/LG9.10.20. X.3923.b RE CAR 6.EX. X.4138. X.4138. A new feature we have fitted to 6.EX Car is the Primer operated from the Instrument Board. Mr. Royce will remember that on this car it was most difficult job to get at the primer tap on the dashboard. The parts used for fixing up this primer operated from the dashboard have been made without drawings because none were available. We found one difficulty in operating the primer on the dashboard. The difficulty comes about due to us having a non-return valve on the hand pump and a non-return valve on the induction pipe. This means that whatever pressure is necessary to lift the valve on the induction pipe, that pressure remains in the leading pipe from the priming cock through the carburetter. We find that this pressure is sufficient to prevent the ball valve in the floatchamber allowing petrol to leak through. We have overcome this trouble by arranging for a slight air leak in the pipe. This means that when we prime we lose a tiny amount of air through the leak but between the strokes of the Hand Pump the pressure falls and allows petrol to leak through the valves in the float chamber. Hs.{Lord Ernest Hives - Chair} | ||