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 oil filter sludging on the Phantom III tappet mechanism, comparing Castrol and Prices engine oils.
| Identifier | ExFiles\Box 144\1\ scan0243 | |
| Date | 28th September 1936 | |
| Your letter is referred to BY RECEIVED 29 SEP 1936 Re Phantom III...Sludging up of the Filter of the Tappet Mechanism. ------ With reference to your recommendation that we should advise only Castrol for the time being, as Prices is more liable to sludge, this will be very awkward, in view of the fact that since the beginning we have advocated Prices engine oil and no doubt large numbers of our customers keep supplies in stock. JLE.{J. Lee Evans - Chassis Test Manager} however, reports this morning that on 3-AZ-24..Barker Trials, he found the filter was very dirty after 500 miles. They cleaned it up but did not change the oil, and have recently examined it again after a further 500 miles have been covered. They found the filter was practically as clean as it was after they had cleaned it, so that it would appear that the initial sludging is very much greater. Is there any means of proving this, because if it is so it might be easier for us to tell customers to examine the filters after the first 500 miles as there is a possibility of sludging taking place, rather than telling them they must not use Prices oil? There is always the possibility of other oils being similarly affected to Prices, and customers not always being able to get Castrol. C. | ||