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).
Engine test, detailing issues with rocker box flooding and carburetter vibration.
| Identifier | ExFiles\Box 43\1\ Scan051 | |
| Date | 19th August 1924 | |
| R.R. 493A (20M) (D.A. 652 20-3-24) J.W.D. EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}3/LG19.8.24. two hours preliminary test on the bed and then dismantled. On re-erecting it was again run on the bed to check power and consumption. These being O.K. the engine was fitted on F.Hangar and given a 40 hrs. run with an 'Aircraft' tractor propeller and 10 hrs. with a pusher propeller. The propellers were cut to give 1800 r.p.m. at 9/10ths. throttle position, this gave a full throttle reading of 1885 r.p.m. REMARKS ON THE TEST. Camshaft Cases. From the commencement of the test on the Hangar the Rocker Boxes were flooding badly. To try and overcome this the size of the feed jet was reduced to .062" dia. This affected an improvement but did not prevent the flooding altogether. Note :- With this small size jet there was ample lubrication for the Camshafts. When the pusher propeller was fitted the flooding was eased considerably - Nos. 2, 3, 4, 5 and 6 Boxes on each side were quite dry but the No. 1's were flooding. Carburetters. By fitting the stays on the bottom of the carbs. the vibration was slightly reduced but not eliminated. After running 20 hrs. the throttle and mixture controls became very slack especially the bell crank lever that is pivotted on the side of the bottom half crankcase. The clearances allowed on these controls should be tightened up. This trouble of slack controls and levers is to be met with on ordinary production engines. contd :- | ||