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).
Bearings, shims, and the composition of crankcase bearing material for chassis B.74.GA.
| Identifier | ExFiles\Box 146\3\ scan0226 | |
| Date | 12th December 1936 | |
| 12451 W/P. Sr. from Rm{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}6/R.12.12.36. Re : CHASSIS B.74.GA - Mr. P.Le BLAN. Replying to your Sr/VA.6/GM.10.12.36. on this subject, we should like you to send all the bits and pieces of the bearings back to us so that we can have a look at them. We have been very short of R.R.56 shims, but I managed to get 3 sets away to you. It is difficult to pass an opinion on No.2 crankpin without seeing it. We recommend that you subject the crankcase to an oil test with the connecting rods in place, and if the flow from No.2 bearing is not excessive, then there is no need to re-grind the shaft. The crankcase bearing is R.R.50. Its composition is :- Copper ........ 0.80 - 2.00% Nickel ........ 0.80 - 1.75% Magnesium ..... 0.05 - 0.30% Iron .......... 0.40 - 0.80% Titanium ...... 0.05 - 0.25% Silicon ....... 1.50 - 2.80% Aluminium ..... Remainder. With regard to the repair job which is being carried out by Maurice Martenet. The logical way to prove the quality of repair is to get this crankcase on one of your trials cars, and run mileage on it. Rm.{William Robotham - Chief Engineer} | ||