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).
Testing A-C sparking plugs type No.114-Q in F.11 engines.
Identifier | ExFiles\Box 79\2\ scan0192 | |
Date | 17th April 1928 | |
X1026 To RG.{Mr Rowledge} from Hs{Lord Ernest Hives - Chair}/VH. Hs{Lord Ernest Hives - Chair}/VH1/LG17.4.28. A-C SPARKING PLUGS. X.1026? X4425 Type No.114-Q We have tested some A.C. sparking plugs as above in one of our 7/1 compression F.11 engines. The plugs are of a non-detachable type with pot insulators and seem to be reasonably good from the point of view of not oiling up readily. We find however, that they run too hot for our F.11 engines, and do not compare favourably with the plugs we have in use at present, as standard - Lodge A-30. The insulators do not appear to withstand the high temperature conditions in our 7/1 engines at full throttle - the cement around the central electrode disappears and we have one case of a fractured insulator resulting. The lower portion of the insulator is loose on the central electrode. | ||