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).
Test runs of the Goshawk 11 engine, detailing issues with the clutch trunnion and concerns about cylinder studs.
| Identifier | ExFiles\Box 180\M1\1\ img014 | |
| Date | 11th August 1921 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to E.{Mr Elliott - Chief Engineer} c. to Du. c. to BY.{R.W. Bailey - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} ORIGINAL X4719 *GOSHAWK 11* ENGINE. Apart from the ordinary test running at various speeds and loads, we have run this engine for 3 8-hour runs at 2000 R.P.M. full load developing 45 HP. During these runs we have had no trouble and we have not found it necessary to adjust the tappets. We expect tomorrow to partly dismantle the engine to inspect it and at the same time to fit pistons to give slightly lower compression for trial, also stronger clutch springs, also to examine the clutch trunnion. I realise I was quite wrong in assuming the sleeve should remain stationary. It is surprising, however, the amount of trouble we have with clutch trunnion thrust races. Goshawk 1, has destroyed a thrust race on one occasion - it commenced to squeal and fired up under ordinary conditions of running. Examination did not show anything was obviously wrong. The Hawk-Northcliffe has also given considerable trouble with the clutch trunnion thrust bearing. We are afraid we have not much information as regards why these bearings fail. We are sending to W.W. today some sample cylinder studs and suitable spanners. We do feel rather concerned about these studs because we realise it is not an easy modification to make and therefore, if they cause trouble after we have embarked upon production, contd:- | ||