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).
Issue with an oil relay lever fouling a piston and subsequent adjustments.
| Identifier | ExFiles\Box 65\1\ scan0157 | |
| Date | 1st May 1926 | |
| To BY.{R.W. Bailey - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to BY/SS.{S. Smith} x8685 Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/LG14.5.26. OIL RELAY. We understand that the Works have been bending the relay lever to prevent this fouling the top of the large piston. As far as we can recollect it was not found necessary to do this on the first relays passed off production. We understand that since then an adjustment by means of washers has been made to ensure that the cam is located in the middle of the contact breaker. This adjustment lowers the zero position of the lever. The fitters in the Expl: Dept: seem to consider the location of the skew gear driving the governor lever to be the most important adjustment required. The fact remains that we have not experienced the trouble complained of ourselves, possibly owing to the differ- ent methods of fitting. We are aware, however, that there is very little clearance between the lever neck and piston (see Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}1/LG2.1.24 to BY/SS{S. Smith}). The drawing scheme 766 shews a very definite foul before the exhaust port can be opened by the inner piston. This however is mis-leading, because as soon as the inlet port is closed, there is no pressure beneath the relay piston and twenty pounds due to the spring on the top so that the large piston starts to fall, oil escaping by the leak round the small inner piston. Therefore, retardation can actually commence when the large piston is in the position indicated by the green line. contd :- | ||