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).
The investigation and replacement of HP valves in front shock absorbers due to leakage and bent stems.
| Identifier | ExFiles\Box 68\2\ scan0243 | |
| Date | 6th May 1929 | |
| 46520 REF 16 May 6th, 1929. TO: Mr. Olley cc - Mr. Burton Mr. Ingham Mr. Bagnall Mr. Humpston Mr. Caswell Mr. Knapton Mr. Soutter Mr. Poole Mr. Ross Mr. Hives (Eng.) FROM: Mr. Fuller RE FRONT SHOCK ABSORBERS Section 7160 Further to RHF'5 of May 6th on this subject, we have removed the HP valve from the right shock absorber of 184-FR on which leakage time was 3 secs. On replacing it with valve A-12294, the leakage time was increased to 9 secs. Another valve A-12293 was then put in, with which the leakage time was found to be 5-2/5 sec. Examination of the original valve showed that the stem was bent. Other valves were also found in Mr. Buckley's department with bent stems. It is evident that this bending is done in milling the flats on the stem, as for this operation the valve is held by the pip on top of the head. It is recommended that some other means of holding be devised, and that the drawing of all valves be altered to show a limit of a 1/2 thousandth out of truth between the seat and the stem. Trial of the riding quality of 102-FR shows almost entire freedom from pitching. This is now evident only on the roughtest roads, and is held to such a small amplitude as to be noticeable with difficulty. This is the complete car in which two standard valves A 12293 were fitted (one of them being a new valve) putting the leakage time up to 6-1/5 seconds, on both sides of the car. RHF. | ||