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).
Retention and potential redesign of the radiator steam valve on the Phantom III model.
| Identifier | ExFiles\Box 94\3\ scan0228 | |
| Date | 25th June 1937 | |
| To E.{Mr Elliott - Chief Engineer} from Rm{William Robotham - Chief Engineer}/Std. c. to Sg.{Arthur F. Sidgreaves - MD} c. to E/Ev.{Ivan Evernden - coachwork} Referring to your memos E.1/HP.26.5.37, E.2/HP.21.5.37, E/Ev.{Ivan Evernden - coachwork}2/M.27.5.37 we note that you assume the deletion of the radiator steam valve for the purpose of N.Sch.5136/7. while we admit that it is possible to run a Phantom III. car (fitted with 4 port cylinder heads) without serious loss of water, as was done in the case of 35-EX. in France, we think that we should not dispense with the radiator steam valve on Ph.III. for the following reasons:- (1) With the steam valve correctly set the loss of water is nil - a feature which we think is desirable on our cars. (2) The steam valve helps us with overheating troubles since it provides an extra margin of safety before water loss occurs (5°C. higher critical air temperature.) (3) We think that the sealing of the cooling system helps to prevent corrosion taking place in the water system - we have no definite proof of this (we are endeavouring to settle this question) other than the fact that 34-EX, the car which cross the Sahara, had a steam valve correctly set and its radiator showed no signs of any blocking of waterways with corrosion product from the engine after 13,000 miles running, whereas 35-EX. which ran 20,000 miles in France, showed definite signs of corrosion deposit in its radiator waterways (although this was not sufficient to cause overheating at this mileage.) However, we think that the steam valve might be made simpler and cheaper and that we should try some simple scheme such as a spring loaded ball or poppet valve - this could be situated in some position other than the present steam valve position and so not interfere with N.Sch.5136/7. Rm{William Robotham - Chief Engineer}/Std. | ||