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).
Modified push rod with a deeper top cup for the Bentley 111 and Wraith III.
| Identifier | ExFiles\Box 100\3\ scan0014 | |
| Date | 13th December 1938 | |
| BY/NS.{Norman Scott} c. Rm.{William Robotham - Chief Engineer} c. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} 454 Hives Files DA.{Bernard Day - Chassis Design}2/G.13.12.38. BENTLEY 111 - PUSH ROD WITH DEEPER TOP CUP. Please receive herewith :- E.CD.1096 Modified Push Rod and Adjusting Screw - Bentley 111 and Wraith 111. The object of this scheme is to prevent the ball end of the adjusting screw from jumping out of the push rod cup in the case of a valve sticking open. The depth of the cup is increased from .175 to .350" which gives an excess of cup depth as compared with cam lift on the Bentley 111 of .037". It is necessary to lengthen the adjusting screw in rocker arm to clear the top rim of the deeper cup on push rod, the centres of the spherical ends of rod being altered to suit. The longer screw alters the geometry of the rocker motion slightly, and causes the push rod in the valve closed position to approach the water jacket tube in the cylinder head rather closely, it would probably be advisable to use the modified water jacket tube E.CD.775 on future engines when this design E.CD.1096 is used. Will Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} please give his recommendations on this point before the cylinder head is altered to include the increased clearance tubes. Will you please detail and instruct the parts experimentally. DA.{Bernard Day - Chassis Design} | ||