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).
Performance of different materials for valve stem washers.
Identifier | ExFiles\Box 19\4\ Scan070 | |
Date | 25th June 1930 | |
To: Wks. c. Hs.{Lord Ernest Hives - Chair} c. By.{R.W. Bailey - Chief Engineer} From: Oy. c. M[REDACTED] X77 Oy4/DM.{D. Munro}25.6.30. Valve stem washers. Sec.5060. With regard to packing washers for the valve stems, I believe felt washers are still being used on P.II. We have found these troublesome in the past as they dry up into a "biscuit" in a few thousand miles especially if car is boiled. We first used "grummets" of graphited asbestos at Mr. Hulley's suggestion about 18 months ago, and found them excellent. At Mr. Bailey's suggestion we have since stopped using graphited asbestos and have substituted plain white asbestos. Btn. reports that there are no complaints of loose guides or stuck valves, or "top-overoiling" with these washers and that they appear to be in every way satisfactory. With these washers it is not so necessary to make the valve spring bottom washer bed down on to the valve guide to hold it in, but we consider it desirable to do so, and I believe this change is contemplated on P.II. OK. | ||