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).
The corrosive effects of leaded fuels on aluminium crankshaft caps and a suggestion to nickel plate them.
| Identifier | ExFiles\Box 150\1\ scan0289 | |
| Date | 25th March 1937 | |
| Files Rm {William Robotham - Chief Engineer} /Grys. Mx. {John H Maddocks - Chief Proving Officer} Hd. {Mr Hayward / Mr Huddy} C. Hs {Lord Ernest Hives - Chair} 1282 BY.7/G.25.3.37. CHASSIS. RE: USE OF "LEADED" FUELS. -------------------------- The crankshaft journal and crank pin oil caps are made from ordinary aluminium bar. We have found on the aero engines that aluminium in any form is seriously attacked by the products of combustion and T.E.L. which work down into the crankcase and therefore the oil. I attach hereto for Rm {William Robotham - Chief Engineer} /Grys. a typical sample of an unprotected crankpin oil cap, which shews how the leaded fuels in an aero engine attack aluminium, the material is RR.56. The practice in aero engines is to completely plate the caps with nickel to a thickness of .002. I suggest that we need to protect the oil retaining caps on 25/30 Bentley and Phantom lll. BY. {R.W. Bailey - Chief Engineer} | ||