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).
Fuel distribution tests comparing a standard induction pipe with one fitted with weirs and bottles.
| Identifier | ExFiles\Box 50\3\ Scan159 | |
| Date | 18th August 1921 | |
| contd. -2- Hs{Lord Ernest Hives - Chair}4/LG18.8.21. amount in the bottles was 2 teaspoonfuls. It is when starting up from cold that we collect the most amount of liquid petrol in the bottles. This, of course, is practically impossible to avoid with low grade fuel. We find, with the Pilot Jet, if it is used intelligently we collect about 10 to 12 teaspoonfuls starting up from dead-cold. If it is not used intelligently, of course, a lot more petrol is collected. We have got Mr. Hall to take a distillation test of the liquid which we collect in the bottles compared with the fuel in the tank. Attached is a copy of Mr. Hall's report. The liquid we collect in the bottles is deep yellow in colour. These tests show that it is the heavy liquid which is always collected in the bottles. The light fractions of the spirit are vapourized and taken right into the engine. It was noticeable on the test bench that with the induction pipe fitted with weirs and bottles. the distribution was excellent. With a perfectly cold engine with low grade fuel we could maintain a steady torque. If we took the bottles away then after a short time when the petrol had reached the level at the top of the weir, the engine would commence to run irregularly and throw out clowds of black smoke from some cylinders. With our standard induction pipe, we found it was only on very rare occasions that oen ever got any liquid petrol in Nos. 1 and 6 cylinders. It varied on different pipes which of 2, 3, 4 and 5 cylinders obtained the most liquid petrol. contd:- | ||