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).
Technical memorandum regarding issues and correct procedures for the erection of engine gears.
| Identifier | ExFiles\Box 75\1\ scan0090 | |
| Date | 2nd December 1919 | |
| X3426 chassis BY.{R.W. Bailey - Chief Engineer} from EP.{G. Eric Platford - Chief Quality Engineer} c. to Mr. Swift. " " Scott. " " EH EP{G. Eric Platford - Chief Quality Engineer}4/F2.12.19. RE. ERECTING OF ENGINE GEARS. We have recently had trouble with the above, and I am anxious to bring forward the following points, which should be given careful attention during erection :- 1. The end play of the gears should be correctly taken up. The thrust bearing races appear to spin round on the spigot end of the bronze bearing, causing wear to take place on the packing washer and the bearing itself. To overcome this trouble, we found that on our pre-war cars the races had to be made a tight push fit on to the spigot. This does not appear to be the case with cars on test, whereas according to the drawing it should be so. 2. There is also the end play of the crankshaft pinion. This I dealt with in my memo. to you re. attention to spring drive, ref. EP{G. Eric Platford - Chief Quality Engineer}2/F1.12.19. 3. There is also the end play of the camshaft, which is an important point. It was our pre-war practice to build up the camshaft, bearing, and driving wheel separately, so that the end play could be checked and made correct, which should be between .003" to .005" with the wheel firmly fixed in position. This being satisfactory, the camshaft can then be built in position on the engine. We have certainly had cases on test where the cam wheel has come adrift owing to want of end play. On the contrary, we have had camshafts which have had too much end play. 4. A further point is the correct meshing of the gears. I find that in cases of engine gear noise developing, it has always been due to the original grinding in position of the gears, forming a distinct groove, owing to one gear overlapping the other. End play has developed and allowed this position to be altered, hence the noise. Contd.- [Upside down text at bottom right: R.R. 255 A (1000 12/18) F.{Mr Friese} S. (P.) 579, (6/4/19) C. 2354] | ||