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).
Secret memo on the revised specification for the 'Japan 3' engine, detailing proposals for the cylinder block, crankcase, and cylinder head.
| Identifier | WestWitteringFiles\V\March1931-September1931\ Scan114 | |
| Date | 13th April 1931 | |
| HY.{Tom Haldenby - Plant Engineer} FROM E.{Mr Elliott - Chief Engineer} SECRET. El/M13.4.31. C. to SQ. LDR. HS.{Lord Ernest Hives - Chair} (crossed out) C. to Lt. RHC.{R. H. Coverley - Production Engineer} IA. (crossed out) JAPAN 3. - REVISED SPECIFICATION. XS770 Regarding our meeting on the 9th. and 10th. the following are some notes that I made in connection with the engine. CYL. BLOCK AND CRANKCASE INTEGRAL. We are proposing that if this part in C.I. is unacceptable on account of the extra weight involved it should be made in aluminium with inserted wet liners of nitro hardened austenitic steel or austenitic C.I. A further liner material suggested possessing a high co-efficient of expansion is C.I. and monel-metal alloy. These liners would have a double rubber ring gland with atmospheric groove between. The inserted wet liner saves complicated water jacket coring. The aluminium block would be lighter than our present practice. The integral construction saves much work on the joint between cyl. block and crankcase which now has to be scraped, and avoids cyl. bore distortion, a trouble that has never been entirely eliminated. The integral construction also saves on the height of the engine permitting use of present length of con. rods. The use of high expansion cyl. liners should be of considerable help in avoiding piston knocks and in allowing more extensive bedding faces on piston to be used. Nitro hardened cyl. bores or centrifugally cast C.I. liners would increase durability and facilitate replacement. It is agreed that the machined bore in the crankcase of the present design of J.{Mr Johnson W.M.} 3. for camshaft and bearings is impractical and we have therefore suggested for the integral cyl. and crankcase that there shall be a large external door which shall disclose a chamber housing the whole of the camshaft and tappet bearings. This chamber will hold up enough oil to form a bath for lubricating the tappet gear. Boring is limited to the housings for the camshaft bearings and the boring bar can be supported in between. CYLINDER HEAD. It is agreed that in addition to the improvements already incorporated in the design to facilitate production, that all cyl. stud boss faces and rocker bracket faces shall be brought flush with the face for the rocker cover. In addition to saving work this move improves the quality of the production at the expense of a slight increase in weight. The internal drip lip and metal to metal joint for the rocker cover has not proved successful on our present engines. Leakage of oil and fidgeting of the cover led to the introduction of a cork washer. (1) | ||