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).
Relaying an owner's letter about curing an engine misfire on magneto ignition by replacing spark plugs.
| Identifier | ExFiles\Box 47\1\ Scan026 | |
| Date | 9th November 1920 | |
| R.R. 285a-(100 T) (S.H. 159, 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2850 XC4117 SthH FMSL/SP{Mr Spinney}/9.11.20. 1. H.{Arthur M. Hanbury - Head Complaints} 2. F.W. 3. E.W. Ed{J. L. Edwards} Copies to:- C. Hr.(2) Ms. Er. Memorandum No. 1963. Geoffrey Summers, Esq., Highfield Hall, Northop, FLINTSHIRE. RECEIVED [STAMP with NOV 10 1920] Chassis No. 39-TN. Regd.No. OA-460. With reference to my Report No. 1853 on the above car, in which I reported the owner's remarks about the misfiring of his engine on magneto ignition, I have now received a letter from him with reference to this, copy of which I give below:- Oct. 28th, 1920. [STAMP: Hr 10 NOV 1920 RECEIVED] "Dear Captain Strong, As I promised I am writing to let you know how I am getting on with 39-TN. I believe I have cured the magneto ignition permanently; at any rate to-day I have failed to obtain a misfire at any speed or at any position of the mixture lever or at any temperature of the engine and running light at about 120 revs. the exhaust has almost as even a beat on magneto only as my old pre-war Bosch-equipped car. The secret of the cure is plugs. I have bought 6 new Bosch plugs just delivered from Germany and I am sorry to say I am not ashamed of myself! Since I last saw you my magneto ignition had been getting worse and worse: I rewired all the plugs but no improvement resulted: I recently took delivery of my other chassis 14-MS and as this behaved fairly well on magneto (at any rate better than 39-TN) I changed over: 39-TN was still no better: I then fitted the Bosch plugs and the change was nothing short of phenomenal. I give you my theories for what they are worth:- Lodge plugs are fairly satisfactory when new but they deteriorate rapidly in use. The electrodes seem to | ||