Modifications and specifications for Type Rear Dampers and Ball-Pin Oil Holes on chassis 25-EX.
| Identifier | ExFiles\Box 56\1\ Scan152 | |
| Date | 20th June 1931 | |
| X235 Re. F83611 Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} TYPE REAR DAMPERS. The cast iron end covers used with these dampers have narrower valve seats than standard, thus the valve areas are greater than with aluminium end covers. Consequently the standard washers do not give the required loads. In order to obtain the standard loads on the pair fitted to 25-EX, the H.P. valve was fitted with a "pre-filter" spring F.80991, together with a .075" valve cover washer (deleting the 2 B.A. washer on the top of the spring), the L.P. being fitted with a .040" valve cover washer, in conjunction with the present standard (filter type) F.81369 spring. 83169 These gave standard left-hand loads of 95/115. The H.P. valves were also drilled with two .038" dia. holes. Re. BALL-PIN OIL HOLES - 25-EX. In order to correct the angular position of these holes, a special locating washer, Ex.6443, was fitted to the N.S. damper. The tabs on this washer are inclined 18° from the standard washer F.83580. When the connecting tubes were in position on the chassis, a thin wire was passed right through the oil channels, thus ensuring that the passages were clear. | ||
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).