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).
Investigation into the causes and occurrences of piston rattles.
| Identifier | ExFiles\Box 77\3\ scan0172 | |
| Date | 13th April 1920 | |
| R.R. 235 A (100 T) (S.F 846 6-8-19) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2460 X.3751a To C.J. from Bn.{W.O. Bentley / Mr Barrington} to R.{Sir Henry Royce} from Bn.{W.O. Bentley / Mr Barrington} c. to Wor.{Arthur Wormald - General Works Manager} c. to Hs.{Lord Ernest Hives - Chair} c. to Da.{Bernard Day - Chassis Design} RE PISTON RATTLES. Bn{W.O. Bentley / Mr Barrington}1/W13.4.20. c. to By.{R.W. Bailey - Chief Engineer} c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to EFC. c. to Sft.{Mr Swift} X.2748. X.3751a. The action to be taken in connection with Piston Rattles was further considered at a Meeting between Hs{Lord Ernest Hives - Chair}, EP{G. Eric Platford - Chief Quality Engineer}, and Bn.{W.O. Bentley / Mr Barrington} on Monday afternoon, April 12th. The information on this subject reported by the Experimental Dept. now standard as follows:- (1) Piston Rattles have occurred on three standard engines (one being on the Test Bench and two on the road) in all cases using Castrol as engine Lubricant. (2) Piston Rattles have occurred on 17-CA with standard lubricant but with fine clearances on the top band of the piston. (3) Rattles appear to occur with standard pistons but using Castrol after five to six thousand miles on the road and disappear when the engine is decarbonised. (4) Standard pistons using our standard lubricant (Price's) in most cases show similar but less pronounced markings on the top band to those markings found on pistons which rattle but no cases of piston rattle have occurred. (5) Modified pistons having an extra ring at the top of the piston have been run successfully on Castrol Oil for about 2,800 miles and for 50 hours on the Bench. These pistons show signs of picking up on the narrow top band but it is not thought that any harm could result from this. (6) No modified pistons with the ring at the top have yet been run on standard lubricating oil. From the facts brought forward it is confirmed that no action should at present be taken to modify pistons which have been manu- Contd. | ||