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 from S.U. Carburetter Co. Ltd. discussing sticking piston trouble and float chamber design.
| Identifier | ExFiles\Box 121\3\ scan0106 | |
| Date | 23th December 1940 | |
| TELEPHONE: BIRMINGHAM EAST 1171. TELEGRAMS: FLEXCARBUR, BIRMINGHAM. THE S.U. CARBURETTER CO. LTD. PROPRIETORS:- MORRIS MOTORS LTD. ADDERLEY PARK, BIRMINGHAM, 8. VISCOUNT NUFFIELD CHAIRMAN W. M.{Mr Moon / Mr Moore} W. THOMAS VICE-CHAIRMAN C. SKINNER, M.I.A.E. MANAGING DIRECTOR YOUR REF: OUR REF: BC/IH2. Messrs. Rolls-Royce Ltd., D E R B Y. 23rd December, 1940. For the attention of Mr. Salt, Car Experimental Dept., Dear Sir, Referring to the points raised by you, by telephone last week:- (1) The sticking piston trouble may be caused or aggravated by the two-lug fixing of the Suction Chamber Assembly- but if so it is "a new one to us"; instead of the present zinc piston we would suggest trying a pair of brass ones as these are more stable at high temperatures. Your suggestion of a four lug fixing for the Suction Chamber Assembly is not possible on that particular pressure die zinc carburetter body. Within practicable limits the present die cannot be altered, but, of course, you could have a sandcast "special" body with four lug fixing, at, naturally, an increased price. Incidentally we should also have to put through a new gravity die for the new four lug Suction Chamber. (2) Regarding float chambers for the 2 ½ throttle carburetter it is quite possible to have a float chamber on either side of the body but this means having twin bosses for the chamber fixing bolts, as shown on enclosed detail print 1766 (this is a smaller 2.3/16" dia. throttle carburetter). The present casting 1864 (detail print enclosed) has only one fixing boss, but this pattern can be altered to the twin type. The two float chambers would of course give you a more constant level compared with the single, as well as a big factor of safety from the "flow" point of view. Yours faithfully, For THE S.U. CARBURETTER COMPANY LTD., B.R. Cooper Enclosure | ||