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).
The test procedures for various makes of sparking plugs.
| Identifier | ExFiles\Box 35\3\ scan 129 | |
| Date | 2nd February 1921 | |
| X.4196 To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to Bn.{W.O. Bentley / Mr Barrington} c. to E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to EWT. for R.R.Inc. Hs{Lord Ernest Hives - Chair}5/LG9.2.21. X.1312 - TESTS ON SPARKING PLUGS. X.4295. X.390.5 X.4196. X.4277. Below are the results of tests carried out on various makes of sparking plugs. The tests which each type of plug was subjected to were as follows :- Test 1. Engine run on weak mixture for a long period and then run with full compression to see if misfiring occurred or insulation failed. Test 2. Engine run with over-strong mixture - the engine was run on the road for 15 mins. with primer cock open to see if plugs would soot up. Test 3. Engine run with excess of oil to cylinders - when plugs were removed they were all wet with oil. Test 4. Test bench tests for pre-ignition. Test 5. Test to see amount of gas leakage past packing of insulators. -------------------- Contd:- | ||