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).
Letter to the Zenith Carburetter Co. Ltd. regarding modifications to accelerator pump pistons and carburetter feed holes.
| Identifier | ExFiles\Box 122\2\ scan0269 | |
| Date | 16th November 1937 | |
| x 1033 Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe}10/MH.{M. Huckerby} Messrs. The Zenith Carburetter Co. Ltd., Honeypot Lane, Stanmore, Middlesex. 16th. November 1937. For the attention of Mr. A.E.Palmer. Dear Sirs, 30 HP. D.C.42. With reference to the special leather accelerator pump pistons supplied for test. The pump spindle is too small in diameter for the standard spring to be located properly. This was overcome by fitting a brass bush over the spindle, the outer diameter being .240"; this dimension was originally .218" on the brass piston. The stroke was set (average .300") using the inner hole the length of bush approximately 1.300". This hole is drilled too large in the lever and we would appreciate this being a better fit to the link. Will you please check the limits at this point and if possible fit this type of piston with the modification as mentioned, to those 9 carburetters that have been ordered with special levers. With further reference to these carburetters we still believe that the main feed hole from the floatchamber should be .156" diameter instead of the existing .106". There is no appreciable difference in level drop between the .130" and the .113" seatings. | ||