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).
Examination of an obstructed oil drilling in a B.80 No.6 Crankcase.
| Identifier | ExFiles\Box 124\2\ scan0351 | |
| Date | 11th September 1941 | |
| 1044 To Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/TAS.{T. Allan Swinden} c.c. to Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager} [text struck through] c.c. to Rm{William Robotham - Chief Engineer}/OTS. [text struck through] Rm{William Robotham - Chief Engineer}/TAS.{T. Allan Swinden}1/JH.11.9.41. B.80 No.6. Crankcase. We have examined this crankcase and found the oil drilling to the centre main bearing obstructed for a length of 1" to 1 1/2" in the manner shewn below. [Diagram showing a cross-section of a crankcase with labels 'CYL' and 'cl'] [Handwritten signature 'Rm{William Robotham - Chief Engineer}'] It does not seem likely that disintegrated bearings would cause an obstruction at the top end of the drilling, but rather at the bottom end. The obstructing matter would appear to be either A.{Mr Adams} Moulding sand, or B. Residue from the dope which was used by the Foundry as a treatment for porosity. The crack in the water jacket was present (about 2" long) when the crankcase was first received by the shop. It was then sent back to the foundry for treatment. We enclose the obstructing matter, and suggest that after you have seen it we have it analysed so as to make quite sure where it came from. The obstruction had to be driven out with a hammer and drift, as it was impossible to pass 1/16" dia. steel wire through the hole. Nevertheless there may have been sufficient leak through, or the sand may have been sufficiently porous, to allow a satisfactory flow on a cold oil test. Since this is the only oil feed to the centre bearing and the latter does not feed any crankpins this obstruction may well be the solution to the mystery. Cont'd.{John DeLooze - Company Secretary} | ||