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).
Comparative engine tests, addressing temperature, starting issues, and fuel flooding problems.
| Identifier | ExFiles\Box 101\1\ scan0173 | |
| Date | 27th March 1936 | |
| -2- Hs{Lord Ernest Hives - Chair}/GWH.{George W. Hancock - Head Chateauroux}2/KW.27.3.36. Upon the car returning to the Works, comparative tests were carried out along with 21-G-IV fitted up with exactly the same induction and exhaust manifolds, and with slightly different carburetters and cylinder head. Starting and running the same mileage, the water temperature of 22-G-V and under bonnet temp. were approximately 10°C. higher than 21-G-IV. Upon stopping 22-G-V water went to over 100°C. whilst 21-G-IV remained at 90°C. After a wait of 10 mins. it took 8 seconds to start 22-G-V, with black smoke from the exhaust. 21-G-IV started within 2 secs., but after starting with a clear exhaust a sudden volume of strong mixture issued. The result of this test proved that 22-G-V is running hotter than 21-G-IV, both water and under bonnet. As the result of the fourth test, i.e., removal of the union in the float chamber, was so consistently good we have devised a scheme whereby we retain the breather and provide means to drain away petrol in case of flooding. The device takes care of a full flow, such as would occur with a punctured float, see sketch. We consider that this scheme gets over our present troubles. Tests have been compared with the Ex.18316 induction pipe under the same conditions. We could not reproduce any failure to start when hot with this pipe. The exhaust was clear. We considered that the slow running was more even. The fault of this pipe (under conditions that we should regard no customer would ever do) is 10 m.p.h. full throttle, bad detonations, very rough engine. The engine upon opening up after 200 yards misfired due to rich mixture. At 15 m.p.h. it does not occur, and does not occur except when absolutely full throttle is used under the above conditions. Hs{Lord Ernest Hives - Chair}/G.W.Hancock. | ||