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).
Testing and issues with engine 1V. EAC.11., covering the carburettor, oil pressure, ignition, an oil leak, and magneto.
| Identifier | ExFiles\Box 69\4\ scan0269 | |
| Date | 12th January 1925 | |
| ENGINE 1V. EAC.11. The carburetter on this engine is fitted with an air valve spring of a strength recommended by ACL. Though this gives excellent power, it appears to produce an exceptionally weak spot between 600 and 1000 r.p.m. when opening up suddenly. The new pressure relief valve (LEC.1953) has been tested and gives a flow of 2 1/4 pts/min. at 1000 r.p.m. to the timing gears, 3 pts/min. to the rocker shaft, oil temperature normal. We consider that these oil supplies should be adequate. The ignition advance curve has been set to commence rather earlier than the standard 20° B.T.C. - this was found necessary for maximum power. It might slightly effect the flick start as the full 10° A.T.C. retard cannot now be obtained In other respects the curve has not been altered from that of the last engine, as no loss of power was experienced at high speeds due to incorrect ignition advance. The oil leak from the dynamo drive shaft is now very slight. Enlarging the drain hole to the timing case should complete the curve. If this leak still causes trouble it can be removed by attention to the drain holes on the governor weight casing; this will not necessitate the removal of the timing case. The magneto on this engine is the worst that we have experienced for noise and vibration. In addition we have had to make the sleeve work freely to ensure the hand advance working satisfactorily. This has aggravated the vibration on the controls. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||