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).
Tappet clearances necessary to ensure exhaust valve seating.
Identifier | ExFiles\Box 38\4\ Scan051 | |
Date | 19th July 1923 | |
R.R. 405A (40 H) (EL 42 19-7-23). J.H. D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. Expl. No. 2764 REF: Hel/LMS.8.23. best shape, and we should gradually weed the others out. Tappet clearances necessary to ensure exhaust valves seating. Type of Valve. Tappet clearance at normal temperature. Tappet clearance when engine cold. Weight of Valve. Pre-war 45° | .002" | .001" | 6 ozs. 6 drams. Pre-war 30° | .006" | .005" | 6 ozs. 6 drams. Present std. | .009" | .008" | 6 ozs. Present std. 45° seat. | .006" | .005" | 6 ozs. Present std. flat head 45° seat. | .0015" | .001" | 7 1/4 ozs. (Watermark: 1904 MADE AT CROXLEY) | ||