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).
Investigation into a severe oil leak from the ignition oil relay on car 11-EX during a 10,000-mile trial.
| Identifier | ExFiles\Box 71\3\ scan0094 | |
| Date | 3rd February 1926 | |
| S/W Hs.{Lord Ernest Hives - Chair} from CWB. Urgent X8900 CWB1/ED{J. L. Edwards}/3.2.26. RE: 11-EX - 10,000 TRIAL. You will have seen from the daily reports on the running of this car that an oil leak was observed on the 24th January from the casing of the ignition oil relay and battery ignition tower. This leak became progressively worse with each day's running and finally on the 1st February was so bad as to smother the whole of the inside of the bonnet and engine with oil. The oil relay has now been taken down and examined working, with the cover removed, and has been compared with another on a standard chassis, 89-LC. In the case of 11-EX, there is a considerable steady outflow of oil from the top of the small plunger and if the accelerator pedal is alternately depressed and raised, the oil level on the outlet side of the relay builds up very rapidly until in a very few minutes it overflows from the chamber. In the case of 89-LC, with steady running conditions there is only a very slight leakage from the small plunger and if the accelerator pedal is alternately depressed and raised, the oil level cannot be made to reach higher than about half way up the outlet orifice from the oil relay into the ignition tower. The only differences which have been observed between the two are that the central plunger on 11-EX is much slacker fit than in 89-LC and that the 8 holes through which the oil drains out from the bottom of the ignition tower are 3/16" in diameter and are bored through a boss in an upward direction, instead of being 1/4" in diameter drilled straight through the bottom of the casing. It is presumed this difference is the scheme for exclusion of cranked chamber gasses from ignition governor and distributor drive to L.E.C.2121, Method 2. It would not appear that there is a sufficiently free escape for the oil from the relay, although no explanation can be given for the fact that no leakage of any sort was observed until the car had run 5,600 miles and that from then it has very rapidly become progressively worse. It is, however, impossible to carry on in the state in which it is at present and I should be glad if you would telephone me as near as possible to 10.30 to-morrow morning, so that you can let me know what you would wish done and I will instruct N. accordingly. CWB. | ||