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 an oil leak issue involving valve springs, cotters, and subsequent road tests.
| Identifier | ExFiles\Box 131\2\ scan0241 | |
| Date | 22th July 1938 | |
| -3- Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux}10/N.22.7.38 Cont'd.{John DeLooze - Company Secretary} We then got in touch with LA.{L. A. Archer} who sent us the oil shields for the valve springs. While waiting for these I went further into the matter and found that on the bottom washer or cup for the valve spring, a recess had been turned where the valve stem goes through approx. 1/32" deep and the same amount in diameter of the hole. This I found applied to Phan.III only. In my opinion this leads oil into the cavity of the grummet and should not be there. The valve cotters also were found with the slot at the bottom side when fitted. The valve apparently do not revolve, so instructions were given when re-building up to keep the slot between the cotters crossways to cut out a definate leak down the valve stem. The guards arrived and were fitted. A three hours run in heavy traffic was carried out this morning, and upon returning, a ten minutes idling, before revving up. The amount of smoke issued was to all intents and purposes the same as previously to fitting the drain guards. Examination of the plugs were 50% better than after the attention to rockers reducing oil pressure etc. No.1, 5 and 6 on A.{Mr Adams} bank were still damp with oil and 1 and 6 on B. bank. The condition however, was such, that it was thought they would not cause trouble in the Owner's hands as our test had been excessive. To try and make further sure, we have fitted new bottom spring cups with the recess deleted and at BY's suggestion tinned the hole to make it more or less a fit to the valve stem. This should prevent no more than a film of oil to pass into the grummet which should then be capable of dealing with it. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} | ||