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).
Failures of chassis and engine components during endurance testing.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan25 | |
| Date | 1st July 1925 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. -3- Expl. No. REF: He/LS/LCS:7.25. Two opposite corners of N.S. flange of front of 6th. cross member cracked after 52 hrs. other two holding for remainder of test. One side of flange (of starting handle cover tube) which bolts up to 5th. cross member (directly under radiator) broken off after 42 hrs. 58 mins. New tube fitted, this was found badly worn due to two 1/4" bolts stretching slightly and allowing tube to be shaken up and down in cross member - running 21 hrs. This being replaced by another tube one side of bolting & flange again broken off after a further 23 hrs. 42 mins. Considering that this tube has to support front part of engine, and that it is necessary to be bolted up absolutely rigid, it would probably be an improvement to strengthen up flange and to fit 5/16" bolts in place of present 1/4" bolts. Engine suspension 'U' tube broken on N.S. arm and just to front of front engine foot after running 42 hrs. 58 mins. During the test 7. N.S. rear engine foot bolts broke, average life being 15 hrs. 20 mins. and 3 O.S. bolts, average life being 35 hrs. The bedding of the feet on this particular chassis is bad and no matter how tight the bolts are - contd :- | ||