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).
Advantages and disadvantages of moving the oil pump drive to the centre of the engine.
| Identifier | WestWitteringFiles\J\April1923\ Scan13 | |
| Date | 27th April 1923 | |
| ORIGINAL. S E C R E T. TO R.{Sir Henry Royce} FROM E.{Mr Elliott - Chief Engineer} E1/M27.4.23. c. to-CJ. HS.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. RE. OIL PUMP DRIVE BEING MOVED TO CENTRE OF ENGINE. X9160 Regarding the above, apart from allowing us to use the most desirable position for the starter motor, this appears to have the following advantages:- (1) It is easier to hob the oil pump gear wheel and grind the cams on the camshaft. There is 1" more room. (2) No set screws and bushes are required in the crankcase in place of studs for securing valve tapper covers. (3) Shorter oil pipes generally. (4) More effective ground clearance, i.e. oil drain plug more forward. (5) More room for lubrication trough to camshaft bearing. (6) More room round camshaft bearing. (7) The oil relief valves rather more accessible as they come between the rear end of front spring and beginning of tie rod. The disadvantages are:- (a) We have to introduce a short suction passage in the base chamber as shewn on the attached blue print LeC. 1711. (b) We bring the features of the oil pump and strainer which partly interrupt the continuity of the crankcase opposite the maximum bending moment instead of in the vicinity of the maximum. This does not look so dreadful as it sounds. Subject to your final decision on this point we are proceeding with the central position of the oil pump which you originally suggested in connection with accommodating the front brake gear. E.{Mr Elliott - Chief Engineer} | ||