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 issues including excessive oil consumption, poor idling, and oil pressure failures.
| Identifier | ExFiles\Box 130\2\ scan0087 | |
| Date | 10th August 1936 | |
| -2- (1) Excessive oil Consumption & Overoiling of plugs. The latter is most serious and is causing dissatisfaction amongst the various owners. It is difficult to deal with, as these owners use their cars in London only, and there is little chance of running the engine at a high speed to burn off the accumulation of oil getting past the rings. When there has been available time, these cars have been given a short, fast run, which completely dried up the excessive oil, with the result that even running was obtained and no misfires. Cricklewood have diplomatically dealt with these owners, but the position is not satisfactory. Existing and future complaints will be dealt with by L ring. See (2). (2) Excessive oil consumption. Although the complaints of heavy oil consumption are numerous, the situation is not as serious as the overoiling; generally these owners are using their cars on long runs, and an explanation to them that it will improve has in most cases satisfied the owners. Tests have now been carried out with an 'L' shaped ring fitted in the centre position. This has improved the oil consumption by 500 M.P.H. Arrangements are being made to supply Cricklewood with these rings to fit to cars that are overoiling and any recurrent complaint of poor consumption. See Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/MJ.8.8.36. (3) Poor idling of Engine. The idling of the engine is not good. It will not remain consistent. The fault appears to be due to building up, on richening up, periodically. One fault we have found is over-richness of the low speed jet. This appears to become strong after approximately 1,000 miles' running. It is possibly due to the piston rings bedding in, which cuts out air drawn into the cylinder past the piston. The setting of the jet after this mileage appears to remain more consistent and better idling is obtained. It does not, however, overcome the periodical misfire. This appears to be due to heavy petrol collecting in the induction pipe. It has been agreed to set the carburetters slightly weaker to allow for the strengthening up. (4) Failure of Oil Pressure. There were three cases of this due to sticking release valves. When examined, the burrs caused when fluting the stems had not been cleaned off. This caused the valve to jam in the barrel. The oil pressure in all cases was steady after attention to the valve stems. At the suggestion of Sft.{Mr Swift} I have examined at random 6 release valves at the Works and in each case there were no signs of burrs. The faulty ones reported must have inadvertently been fitted. | ||