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).
Technical report page detailing investigations into engine piston knock, valve clearance, gear rattle, and carburettor issues.
| Identifier | ExFiles\Box 5a\3\ 03-page312 | |
| Date | 20th June 1933 guessed | |
| - 2 - engine was idling. It could not be heard under load. Examination of the piston did not disclose any definite fault to cause the knock. The only noticeable reason was extra slackness on the non bearing surfaces of the piston and the con rod showed slightly out of alignement with the bore. N°3 piston was located knocking. VALVES & FITTINGS LOP.E.55577. Complete to the above LOP. There has been a loss of clearance in the exhaust valves. The cause being due to hammering in of the seats. The fault has not been serious. The valve springs have been free from swishing noise and no springs have broken. The condition of the valve stems and guides did not show any undue wear. ENGINE GEAR RATTLE The engine gear rattle became pronounced both under load and when running light. Brake blocks are fitted to the dynamo drive. The load on these blocks was increased with no appreciable results. It was then made lighter with much better results, the rattle under load being cured. There remained a light rattle when the engine was idling. CARBURETTER LOP.E.55795. Complete to the above LOP. using E.58392 Spray Chamber in conjunction with Air Silencer (fitted by Expt. Dep.) The result is a carburetter free from any suction noise. The consumption has been on the heavy side, but considerable gear work is responsible for heavy consumptions. Consumptions taken at 30; 40 & 50 M.P.H. do not show any marked difference to the standard carburetter. Oil was being drawn by the carburetter via the breather pipe to the crankcase, and dripped from the carburetter. A baffle chamber was fitted to the breather pipe, which prevented 90% of the oil being drawn into the carburetter. The air valve stuck on several occasions. | ||