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).
Diagnosing intermittent misfiring and pump failure on a 4 1/4-litre chassis.
| Identifier | ExFiles\Box 90\2\ scan0146 | |
| Date | 16th October 1936 | |
| [Handwritten text at top] Dodds. DIXON X 261 K/KC/DPB/16.10.36. We must get hold of these plugs and try them. Why not revert to standard. We must also get hold of pumps D Please file [Typed text] K/W. Hs{Lord Ernest Hives - Chair}/GH. Chassis No. B.34.GA. Professor Dodds. The above 4 1/4-litre (which I believe has been in the hands of the Experimental Department for misfiring at low speeds) was brought into K today by the owner's chauffeur with the following complaints. (1) Intermittent misfiring at low speeds - that is to say, top gear, range 10/20.m.p.h. (2) Pump failure when hot. This has happened twice since the pumps were changed. For your information I give below the elimination test carried out by us before changing the plugs:- (a) The car was tested with a temporary set of high tension leads in case the originals proved faulty. This had no effect. (b) The condenser unit was changed, with no result. (c) The A.C.plugs type X.399 (single point) were exchanged for K.L.G. type 927, which the chauffeur carried as spare. The misfiring was immediately cured. No attempt was made to interfere with, or clean the plugs, as we were not sure whether the Experimental Department wished us to do so. They were therefore returned to the chauffeur in the condition in which they were removed from the engine. The mileage is now 8315 and I am given to understand by the chauffeur that he has covered 215 miles since the change over of plugs etc. was made by your man Dodd. Regarding the pump failure, these pumps were fitted at W. on the 2.10.36. -contd- | ||