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 condition of sparking plugs and a dynamo, with a request for a new dynamo belt link.
| Identifier | ExFiles\Box 109\4\ scan0185 | |
| Date | 5th August 1939 | |
| EDWARDS 666a To. Rm.{William Robotham - Chief Engineer} (The following two lines are struck through in red) c. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} c. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} CHATEAUROUX. 4/5.8.39. [Handwritten note:] let me know about the belt Rm{William Robotham - Chief Engineer} 30.G.7. Electrical Equipment. SPARKING PLUGS. Three Champion N.8. plugs have been removed with the central electrodes burnt right away at 11,386, 12,753 and 12,920 miles. The other five plugs have burnt from .020" to .035" in 12,920 miles and have also been removed as the central electrodes are fairly badly eroded. We are returning all these plugs for your inspection. The life appears quite reasonable considering the performance of the car and the high speeds at which it has been driven. We have fitted the set of Champion N.A.10. supplied, for further test. DYNAMO. Intermittent charging when hot began to occur. We removed the dynamo for inspection and found a gummy deposit on the sides of the brushes which may have been making them stick. They are otherwise in good condition however, and the wear is negligible for the mileage. We have however, returned them to you so you can find what the gum consists of. The commutator had a light patch on it at one place, but cleaned up quite nicely. We have fitted a new pair of brushes for further running. The belt adjustment is now at the end of its travel but the tension is good, and it should last the mileage. We should be interested to know how much more the belt could be adjusted as slack develops before it breaks. For this purpose will you please make and send us a link with a longer slot in it. Rm{William Robotham - Chief Engineer}/IMW{Ivan M. Waller - Head of Chateauroux} [Signature:] Jwaller | ||