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).
Proposal to test different carburetter bodies and their associated starting mechanisms.
| Identifier | ExFiles\Box 122\4\ scan0194 | |
| Date | 4th October 1938 | |
| -3- A recent test has shown that if we deleted the drain, the height of the lamp post would have to be extended to three feet, to counteract the high pressure pumps in the case of a full bore flood. Finally, it is proposed to settle the question of finish in the following way. We are obtaining two carburetter bodies from Zeniths. One to be identical with the sample (no. on the attached photograph) and another taken from present production stock. These will be handed to our Laboratory to carry out an accelerated side by side wear test, to show heat resistance etc. The difference between the carburetters on the photographs is as follows:- No. (1) Standard finish. Hand control starting. No. (2) Cleaned up before enamelling. Hand control starting. No. (3) Finish as No.(1). Automatic starting. Suction controlled bye-pass jet. No. (4) As (3) but with electrical starter unit mounted on carburetter. NOTE. The automatic starting shown on No. (3) requires a separate bi-metal strip unit to be mounted on the exhaust manifold, which as mentioned before, is on the other side of the engine. The automatic starting device of No. (4) works by a bi-metal strip, and a self contained electric heater. The latter comes into action when the ignition is switched on. We do not like this device because:- (a) If the driver delays in pressing the starter after switching on, the choke can be wide open on a cold engine. (b) The electric heater is solely relied upon to keep the choke open for normal running, and the whole unit gets hot enough to blister all the paint off. | ||