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).
Unsatisfactory testing results of Heath spark plugs in cars and aero engines.
| Identifier | ExFiles\Box 33\3\ Scan099 | |
| Date | 3rd February 1921 | |
| X1812a. Hs{Lord Ernest Hives - Chair} AT *FEB 3 1921 H'd.{John DeLooze - Company Secretary} From EP{G. Eric Platford - Chief Quality Engineer} [crossed out] c. to Hs.{Lord Ernest Hives - Chair} EP{G. Eric Platford - Chief Quality Engineer}3/R1.2.21. RE. HEATH PLUGS. RECEIVED With reference to your WD{Mr Wood/Mr Whitehead}6/NJ26.1.21, you can assure Heath Plugs Ltd. that we have not condemned these plugs without complete test having been made. It could be pointed out, if you think wise, that we are anxiously looking out for an ignition plug which can be used satisfactorily on our cars, as we are not satisfied with our present standard, and every attention is therefore given to every ignition plug which appears to be constructed on scientific lines, having regard to our experience in the weaknesses and failures of plugs as used on our cars and aero engines. With regard to running the plugs in aero engines, we are quite satisfied with some of the plugs we are now using, i.e. K.E.G. F.12, and a test was made with the Heath plugs some considerable time ago, it being found that on these engines they were hopeless, and overheated. Our attention was therefore given to testing these plugs on our cars, and we found that with such tests as we gave them they soon oiled up or sooted up and failed, a point which is also quite confirmed by the Experimental Dept. who have recently been giving the question of testing plugs their serious attention. They were emphatic on the point, however, that the Heath plugs were hopeless. If Heath Plugs Ltd. would like us to again test these plugs we will do so, and should we find a favourable opportunity of again making comparisons [we may again test them - crossed out, with 'again test' handwritten above], but at present we must stand by the fact that they have been tested and found wanting. EP.{G. Eric Platford - Chief Quality Engineer} R.R.25A.10M.(100) H&S(P) 18-12-20 GL{G. Linnett} 2047 | ||