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).
Failure of AC.9 material in a Bentley Chassis B.125-JY, owned by Sir James Heron Walker.
| Identifier | ExFiles\Box 114\3\ scan0017 | |
| Date | 9th February 1939 | |
| BY.{R.W. Bailey - Chief Engineer} c. RHC.{R. H. Coverley - Production Engineer} c. BY/SB.{Mr Bull/Mr Bannister} Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux}19/C.9.2.39. BENTLEY CHASSIS B.125-JY. MILEAGE AFTER MOD. C. 1061. OWNER - SIR JAMES HERON WALKER. (AGE APPROX. 25). FAILURE OF AC.9 MATERIAL. The above car has failed after a Mod. C. which was carried out 4.1.39. The failure is due entirely to the growing of the metal, and the way the car has been driven, which corresponds to your theory on the AC.2 material. The car has apparently been driven normally for a short period, then from what we can gather was run at maximum speed top and third during a nights run. The bearings having grown, and lost their clearance, heated up, and one, No.4 seized, and broke the metal up. The bearings have been carefully measured up in the rods prior to taking them out, and you will observe on the chart enclosed the three bearings which have not got hold, all the clearance diagonally has been taken up, vertically where the thump takes place the original clearance remains on two of them. The bearings which have partially seized and which must have heated up show the moulding effect of the oil groove in the rod. The main journal bearings have become scored by the metal from No.4 rod. The chart gives the dimensions as they were fitted, along with the present dimension. I am forwarding the con. rod bearings for your examination, along with the remaining broken pieces. GWH.{George W. Hancock - Head Chateauroux} | ||