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).
Engine modifications to improve oil circulation and reduce friction.
| Identifier | ExFiles\Box 96\1\ scan0401 | |
| Date | 14th August 1939 | |
| - 2 - (2). Drill three vent holes in each tappet block to sketch herewith in order to improve the circulation of oil by getting rid of the possibility of an air pocket inside each block as exists at present. (3). Fit a set of Cloudburst hardened tappets, as per Mx{John H Maddocks - Chief Proving Officer}/SB.{Mr Bull/Mr Bannister}5/MG.14.7.39. (4). Fit a set of new floating rocker bushes. (5). Add oil grooves to rocker eccentrics to reduce friction. (we will groove these on a special hand rig which has been made). (6). Check clearance of hydraulic plungers. These should have definite clearance of .00275" to .003". Clean out metering screw passages and oil holes in rocker shafts. (7). The foregoing represents the utmost that can be done at the present juncture, and we are quite sure that a definite improvement should result. We have only been able to confirm any results on one engine, and a good deal of additional running must be done to gain any further experience, and this can only be achieved now on customers cars. We do not wish to use Player's car for experimental purposes, but it presents an excellent opportunity to gain some experience since nothing of the previous standard has stood up, and, in any case, the final result of the modifications proposed cannot possibly be any worse than the last set of tappets. We have handed to Mr. Hurst two worn camshafts of the hydraulic type (E.88127) and these can be stoned up satisfactorily if a new camshaft is not available. We are continuing our tests on this problem, but we have had a set back due to the engine having been used for Perkins car, and we have had more or less to start again, in addition to which there is the knock in Perkins engine. Mx.{John H Maddocks - Chief Proving Officer}/SB.{Mr Bull/Mr Bannister} | ||