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).
Diagnostic memo on faulty battery ignition parts and potential causes for failure on a 20 HP chassis.
| Identifier | ExFiles\Box 57\2\ Scan026 | |
| Date | 5th June 1930 | |
| X5783 To C. from EFC/IBW. C. EP.{G. Eric Platford - Chief Quality Engineer} C. WOR.{Arthur Wormald - General Works Manager} C. N. EFC absent EFC/IBW4/AD5.6.30. X.3485. FAULTY BATTERY IGNITION PARTS X.5783. 20 HP. CHASSIS GYL-61. X2894. Thank you for your C12/C3.6.30. Our experience of coil failure on chassis is that once the coil fails it is impossible to clear the fault without unwinding i.e. there is no intermittent effect. It is very difficult for us to state the cause of ignition failure on a chassis without first hand diagnosis. For instance, the failure might have been caused by (a) Small piece of foreign matter inside distributor shorting condenser. (b) Loose wiring connections to ballast or coil. (c) Loose fuse connections etc. (d) Contact gap too small or closed up. Any of these would cause intermittent failure. It is always the best plan when complete failure occurs to test for voltage with a small pocket voltmeter at the various points along the ignition circuit before removing any units. This will show the presence of any bad connections and indicate the components at fault. The only other thing we suggest you might have examined on GYL-61 is the H.T. wire from the coil to the distributor. This may have punctured through, due to touching the governor or distributor tower casing. The coil in question has been further tested on an experimental 20/25 chassis with no sign of failure. We have had a case of misfiring on the "pick up" on a customer's 20/25 chassis at the works today, which, upon investigation we found was due to the contact gap | ||