Case studies and observations on resolving engine overoiling issues.
| Identifier | ExFiles\Box 47\1\ Scan427 | |
| Date | 25th November 1927 guessed | |
| Engine Overoiling. Continued. - 5 - 3...6-HC.Overoiling complaint.Fitted set of "Brico"rings,pistons peaned out & refitted. Car tested but overoiling was on the heavy side.Fitted 2nd set of "Brico" rings & reduced big end liners.Car tested & found O.K.Suggest 2nd set of rings cured 85 % of trouble & reducing the liners assisted 15% 4..-46-FC.Engine overoiling.Fitted set ofBrico rings.Pistons refitted to cyl.bores & big end liners reduced.Car tested,all cylinders with exception of No.5 round to be O.K. No.5 oiling was a shade on the heavy side but plugs were not affected. 5...34-HC.Previous to decarbonizing the engine the oiling was O.K. But after decarbonizing the oiling was very much on the heavy side. To overcome trouble we fitted new"Brico" rings,refitted pistons,reduced big end liners Car tested and found to be O.K. OBSERVATIONS.-Judging by the above Nos. of overoiling complaints,& in NO. it would appear that we have not been in much trouble due to the above.The Quarter previously to the last one,we had quite a few over-oiling jobs to attend to,also for the commencement of the first Quarter 1927,we have had at least 6 of the above jobs to tackle. We find that in the majority of cases the trouble can be overcome by fitting one set of "Brico" rings. As a routine job we have been reducing the big end liners in most cases. we have come to the conclusion that reducing the liners assists,proba -bly {B. W. Bleaney - Bentley Sales} not more than 10 to 15 %.When cars have done a fair mileage we refit the pistons,(not from an overoiling point of view)refitting pistons,we do not think helps in the above respect,but we readjust them so as not to be in trouble with pistons knocks. Only in one case have we had to tackle engine bearings before we could affect a cure.In this particular case the crankshaft was entirely rebedded & the car has since given no further trouble.We have been in trouble with regard to over-oiling after decarbonizing several of the earlier engines about five or six in number,in each case previously to decarbonizing,the oiling was examined and found to be O.K.(& no complaint from owner)but in each case after erecting & testing the above cars were found to overoil very heavily & have only cured the trouble by fitting new Brico rings.We are inclined to think the above is caused by removing the carbon deposits around the edges of the pistons.On overoiling complaints,we always pay special attention to the felt washers of valve stems & note that the (domes) or washers for valves springs seats are drilled etc. etc. | ||
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).