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).
To Bentley Motors Ltd. regarding the tightening of main engine bearings on chassis B.10.GA, including shim adjustments and a proposal for a new reporting tool.
Identifier | ExFiles\Box 146\3\ scan0236 | |
Date | 15th December 1936 | |
Files 1020 To Bentley Motors Ltd. Levallois Derby ................Rm.{William Robotham - Chief Engineer} Sr/VAI2/GM.15.12.36 re: CHASSIS B.10.GA - Baron BRINCARD Total mileage 22327 kms. - Engine bearings We have tightened up the main bearings of this car by stepping the shims as agreed to by you in your memo Rm{William Robotham - Chief Engineer}2/AP.II.I2.36 and your memo on "Bearings" of the 8th. instant, Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} We "stepped" the upper face of the shims of the main bearings by the undermentioned amount, so as to remove slack due to sinkage of the upper halves of the bearings into the crankcase. N°I main bearing shims stepped .0045" N°2 " " " " .0065" N°.3 " " " " .006" N°.4 " " " " .005" N°.5 " " " " .0075" N°.6 " " " " .0075" N°.7 " " " " .008" The writer has evelvod a special tool by which the exact amount of sinkage of the upper half of the main bearings can be measured. With the aid of the tool which we are making pressure can be evenly applied to the two joint faces of a bearing, so that the bearing can be pushed upwards into its housing without distortion; to the bearing, measurements can then be taken which will indicate the difference in height between the joint faces of the bearing and the machined liner faces of the upper half of the crankcase. The difference will then be recorded and the shims will then be stepped accordingly by milling. We have always felt without the aid of some such tool that a certain amount of guess work would take place which and not to be recommended. As soon as we have made and tried it, we will, if it interests you, let you have the sketch which we have made. We attach a specimen copy of a Bearing and liner report Sheet which we propose to send you each time we attend to the bearings and liners of a Bentley chassis. If you think the sheet should be altered in any way, then please let us have your comments. Sr/VA.V4 | ||