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).
Comparison and recommendation of different anti-freezing solutions for vehicle cooling systems.
| Identifier | ExFiles\Box 151\3\ scan0150 | |
| Date | 14th March 1931 guessed | |
| COPY. Depot sheet No. Hm.{Capt. W. Hallam - Head Repairs}127. ANTI-FREEZING SOLUTIONS. At the present time the only anti-freezing solution recommended in the Instruction Book is de-natured alcohol. The disadvantage of this liquid is that it evaporates and so the protection is neither permanent nor constant. Two liquids that are not subject to this disadvantage are Glycerine and Ethylene Glycol. Attached is a chart showing the protection which various percentages of these solutions give against frost. The water capacity of the 40/50 HP. is approximately 7 1/2 gallons, the 20 HP. 4 gallons. Therefore a 30% solution for the 40/50 HP. is 2 1/4 gallons of anti-freezing added to the system, and 1 1/4 for the 20 HP., and this should give immunity from freezing under all normal conditions in England. We recommend that when the solution is added the water system should be drained. The Glycerine or Glycol should then be thoroughly mixed with an equal quantity of water before being introduced into the radiator. The reason for this is that the undiluted liquids are likely to loosen scale from the inside of the cylinder blocks which may eventually cause obstruction in the radiator. The rubber joints should be carefully examined before filling with anti-freezing solution and if perished should be replaced, as Glycerine has a searching action which is likely to open cracks in perished rubber. A commercial form of Glycerine on the market is Rad. marketed by Messrs. L.P.P. Pearce Ltd., 50, Mark Lane, London, E.C.2. Ethylene Glycol can be obtained from Imperial Chemical Industries Ltd., Morley House, London Road, Leicester. A commercial form of Ethylene Glycol is sold under the name of Prestone and is marketed by Chalas and Sons Ltd., Finsbury Pavement House, Moorgate, E.C.2. On the whole we think that Ethylene Glycol is preferable to Glycerine as it is not so viscous and is more efficient. Hm.{Capt. W. Hallam - Head Repairs} | ||