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).
10,000-mile trial of Castrol lubricating oil, detailing engine condition and chemical analysis.
| Identifier | ExFiles\Box 32\3\ Scan024 | |
| Date | 19th March 1915 guessed | |
| 41583 10,000 Miles on Castrol. X Interesting Data provided by a Searching Test of Lubricating Oil. AN extremely interesting and instructive publication is the R.A.C.'s official certificate of a recently completed 10,000 miles' trial of Wakefield Castrol R.R. engine lubricating oil. The trial was conducted on a 40-50 h.p. Rolls-Royce, 1915 model, fitted with an open touring body, and the fuel used was National benzole. Unladen, but ready for the road, the car weighed 2.3 tons, the average running weight of the car, including load, being 2.4 tons. Condition of the Eng'ne after the Trial. The trial was over the Club's six standard routes, and the average running speed was 19.9 m.p.h. Upon the whole, the road conditions were good, but rain or snow fell on twenty-four of the sixty-one days occupied by the trial. The engine lubricating oil consumption worked out at 935.25 miles per gallon, which was equivalent to 2,249.5 ton miles per gallon. Both before and after the trial the engine was dismantled, its condition subsequent to the completion of the 10,000 miles being exceedingly satisfactory. Deposit on the piston heads was uneven, being slight over the greater part of the heads, but somewhat heavier on the sides remote from the valves. Both valve stems and valve faces were in good order, and there was no measurable wear of the stems, the same being the case as regards cylinders and pistons. The piston rings generally were in good condition, but on two pistons the top rings were not quite free in their grooves owing to a hard deposit. The sparking plugs, which were neither cleaned nor changed throughout the trial, were found to be in excellent order. Chemical Effects. Chemical investigation of the Wakefield oil before use and after running, in the case of this sample, 1,050½ miles disclosed the following chemical conditions: Before use. After use. Specific gravity at 60° F.{Mr Friese} ... .9079 ... .9075 Viscosity (Redwood) at 100° F.{Mr Friese} ... 790s. ... 930s. Viscosity (Redwood) at 140° F.{Mr Friese} ... 251s. ... 283s. Flash point (close test in Pensky-Martens apparatus) ... 410° F.{Mr Friese} ... 260° F.{Mr Friese} Free acid (expressed as SO₃) ... 0.07% ... 0.07% Suspended carbonaceous matter ... nil ... 0.06% Benzole ... nil ... nil It was found, in regard to the sample of oil taken as above, after use, that the oil had deteriorated very little, and was in a clean and satisfactory condition. D27 | ||