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 report on front suspension needle bearings, identifying insufficient weather protection as the cause of failures.
| Identifier | ExFiles\Box 95\2\ scan0246 | |
| Date | 15th January 1938 | |
| By: from Rm{William Robotham - Chief Engineer}/Les.{Ivan A. Leslie} c. Hd.{Mr Hayward/Mr Huddy} c. RNC. c. Hs.{Lord Ernest Hives - Chair} ------- 346 also 361 Rm{William Robotham - Chief Engineer}/Les.2/AP.15.1.38 Ph.III. FRONT SUSPENSION NEEDLE BEARINGS. Re. Hd{Mr Hayward/Mr Huddy}/SB.{Mr Bull/Mr Bannister}16/HR.11.1.38 LOWER YOKE BEARINGS. We have examined the needle bearings removed from the lower triangular levers on 3.AX.77, and are quite certain that the cause of the trouble is due to insufficient weather protection for the needle bearing rather than the lack of lubrication. If the glands between the needle bearings and the atmosphere were really good, initial lubrication during assembly would be sufficient. We are producing 6 sets of Duprene rubber glands SCD.18 to replace the present "Perfect Oil Seals", which we realize are unsatisfactory. We intend these units to be positive oil seals and they will be easily interchanged with the present units at a very small cost. The above conclusions are based on the following information:- (a) These bearings have always been in excellent condition on bumper chassis. (b) Both bottom yoke bearings were in very poor condition after French testing on 31.EX. (c) 35-EX. ran in France with the bottom yoke bearing protected by a leather cover on one side of the chassis. The protected bearing was in considerably superior condition at the end of the test. (d) The needle bearings on 3.AX.77 are completely choked due to inadequate weather protection. LOWER PIVOT BEARING. We have had no trouble from the lower pivot bearings on Expl. cars. The pivots from 32-EX. after French testing were in excellent condition. Although 3.AX.77 may be a case where the bijur pump has been neglected, we agree that the oil ducts are very tortuous and that a separate oil feed should be far more satisfactory with practically no extra expense. Even with adequate lubrication there is a danger of water getting into this bearing from a water splash unless there is a Duprene washer between the stub axle and yoke piece. Rm{William Robotham - Chief Engineer}/Les.{Ivan A. Leslie} | ||