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).
AC.2 engine bearing issues related to clearance, oil flow, and seizure under specific conditions.
Identifier | ExFiles\Box 114\3\ scan0048 | |
Date | 11th October 1938 guessed | |
-2- (6) The engines fitted with AC.2. bearings do not show up thump because as stated the metal does not so readily develop looseness in the housing and do not thump, but if the diametrical clearance is not sufficient, the metal clings and drags more than AC.7. and seizures occur. Therefore where an engine has run six thousand miles and over, and shows an oil flow of 4 mins. it can be taken that under normal conditions it will not give trouble. If used under hard driving conditions, the drop in oil pressure due to heat is liable to allow the bearing to drag and seize. In conclusion we should say that the AC.2. metal correctly fitted and correct diametrical bearing clearance i.e. .003" would not have given any trouble. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} | ||