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).
Visit to John Marstons discussing corrosion in the Phantom III engine and potential remedies.
| Identifier | ExFiles\Box 137\3\ scan0128 | |
| Date | 25th August 1939 | |
| 1158 + 1280 To By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to Da{Bernard Day - Chassis Design}/Ev.{Ivan Evernden - coachwork} Em/Ed.{J. L. Edwards}4/JH.25.8.39. Visit to John Marstons. A visit to the above firm was paid on the 24th. instant by Rm{William Robotham - Chief Engineer}/Ed.{J. L. Edwards}, Mr. Steadman, development engineer being interviewed. The following points were discussed. Corrosion in P.III. This subject was investigated in detail by Steadman while at this Works, and the primary cause of corrosion was put down to the electrolytic action between the cast iron hot spot and the aluminium engine. The deposit formed was a combination of iron hydroxide and aluminium hydroxide and formed a cement which was exceptionally tenacious and difficult to remove. A heat treat process was applied to the cast iron boxes after trouble had been experienced with the first cars, but only a slight gain appears to have resulted. Later the material of the box was changed to aluminium which appears to have effected a cure. With regard to clearing choked radiators, caustic soda, phosphoric acid (weak solution) and a vacuum product claimed to give remarkable results were tried with no great success. The Mark VI. block which has water spaces in the region of .055" - .060" is comparable with the old P.II radiators which were relatively immune from choking troubles, all deposit going into the bottom tank. This is rather difficult to understand especially in view of the fact that the water path in the P.II was staggered as against a straight run through for the Mark V blocks. A cleaning agent which was not tried by Steadman but is suggested as being rather good is Zero antifreeze, but this has the disadvantage that if it is put into a dirty engine it cleans all the corrosion out and clogs the radiator. Experiments are to be carried out to determine its exact effect. A contributing cause to corrosion is undoubtedly excessive water loss. This was demonstrated by the Sahara car which suffered no water loss whatever and apparently was in a remarkably clean condition on its return. It is unfortunately not known whether this was due to the quality of the water with which the car was filled originally, or whether chemical action took place in the early stages of running giving a saturated | ||