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).
Jamming issue with the Phantom III Carburetter Accelerator Pump Plunger and providing specifications for a new spring to resolve the problem.
| Identifier | ExFiles\Box 122\2\ scan0064 | |
| Date | 11th September 1936 | |
| To RHC.{R. H. Coverley - Production Engineer} Copy to Mx.{John H Maddocks - Chief Proving Officer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Da.{Bernard Day - Chassis Design} Hs{Lord Ernest Hives - Chair}/Swdl.{Len H. Swindell} X1033 E/PSN.1/MN.11.9.36. EWD/J2 Phantom III Carburetter Accelerator Pump Plunger. A certain amount of trouble has been experienced with the leather on the accelerating pump plunger turning over at its edge and jamming. This appears to be caused by the gland on the spindle preventing the leather and the plunger centralising themselves in the bore. To overcome this trouble we propose reducing considerably the influence of the gland in deciding the position of the plunger in the bore so as to give the leather a better chance of centralising itself. To do this the cork washer should be removed and the spring lightened which will result in considerably less friction between the felt washer retaining cup and the top of the float chamber lid{A. J. Lidsey}, due both to the reduced spring load and the metal to metal contact. We should be pleased if RHC.{R. H. Coverley - Production Engineer} would make up 24 springs to the following particulars to replace E.88274 and hand them to MX.{John H Maddocks - Chief Proving Officer} for test. Inside diameter .344" Wire diameter 28 S.W.G. (.0148) 4 working coils and one extra each end ground square. Load when compressed to .375" to be 2 ozs. Approx. free length .85" E/PSN. | ||