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).
Page describing procedures for fuel testing, including determining potential gum and methods for anti-detonation value tests.
| Identifier | ExFiles\Box 27a\4\ Scan105 | |
| Date | 28th April 1933 guessed | |
| -4- After the evaporation, the outside of the dish shall be wiped dry; the dish shall then be transferred to an oven maintained at 150°C. and allowed to remain there for one hour. After cooling in a dust-free place for 20 minutes, the dish shall be weighed by tare against another similar dish which has been treated similarly but without the petrol, to an accuracy of ± 0.1 mgm. The operations after heating the dish shall be made with the use of metal forceps. Potential gum. 50 ml. of the petrol contained in the glass-stoppered glass flask shall be incubated at 35°C. in the dark for 20 hours. At the end of that time, the contents of the flask, together with acetone rinsings obtained by swilling out the emptied flask with a little re-distilled acetone, shall be transferred to the glass dish described in the previous test, and the amount of gum formed determined by the evaporative method described previously. APPENDIX 2. ANTI-DETONATION VALUE - METHODS OF TEST. The knock rating tests will be carried out on an Ethyl Gasoline Corporation Series 30 engine with the high temperature modifications. The compression ratio of the engine will be adjusted by the shim thickness to give a maximum compression ratio on full throttle with fuel cut off and the engine hot of 190 to 200 lbs./sq.in. gauge. The standard bouncing pin and knock meter equipment will be used for measurement of the knock intensity. An air heater will be inserted between the inlet silencer and the carburetter intake. The conditions during a fuel test will be as follows:- R.P.M....................900 Spark advance...............15° Valve clearance cold........0.002" Spark plug gap..............0.025" Jacket temperature..........150°C. Cooling liquid..............A mixture of Ethylene Glycol and water. Quantity of lubricating oil in the engine.........800 c.c. Intake air temperature......30°C. Fuel - air ratio............The ratio for maximum knock. Bouncing pin contact point gap..............0.008" - 0.012" Bouncing pin circuit Voltage..................Full voltage. Knock intensity.............Engine throttle adjusted to give a reading between 50 and | ||