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).
Testing of a smaller fan pulley to address engine water boiling and loss of water.
| Identifier | ExFiles\Box 24\4\ Scan028 | |
| Date | 12th September 1921 | |
| X766 CJ. from EP.{G. Eric Platford - Chief Quality Engineer} c. to R.{Sir Henry Royce} c. to Hs.{Lord Ernest Hives - Chair} c. to PN.{Mr Northey} c. to Hr. for Works Committee. EP{G. Eric Platford - Chief Quality Engineer}1/H12.9.21. X.4394 - RE. WATER BOILING AND LOSS OF WATER. X.4412 X.1298 X.819. With reference to your instructions at the last Derby Conference, re testing of smaller fan pulley, we have now received a small fan pulley for Mr. Bondheim's car, who is one of the complaining customers re loss of water through boiling. Our standard dynamometer test includes a water heating test, in which we measure the time taken for 5 gallons water to pass from the overflow in order to maintain a fixed water temperature, and in taking this test with the standard and with the small fan pulley, we find the small pulley makes about 50% improvement, with the engine running at 1250 revs. fully open throttle, whereas at 500 revs. 20% improvement is shown. In comparing the horse power absorbed, there was no appreciable difference in the horse power registered by the road wheels on the dynamometer. From these tests it would appear that the smaller pulley does show a distinct improvement, and we are now arranging to confirm these tests on the road. I do not wish to feel that I am recommending the use of the smaller pulley, as with our present high speed engine we already know that the present fan has to be very carefully made, and a proper clearance given for the fan blades, otherwise trouble is experienced with the blades breaking or catching on the radiator, and before adopting such a scheme for a few customers, I feel it is a point on which Mr. Royce should give his consent. If it is a matter of tackling the fan question in order to deal with these emergency cases, it is possible that R.{Sir Henry Royce} will consider using a more efficient fan. In Mr. Royce's memo to you ref. R3/G8.9.21, his action is chiefly based upon that of preventing loss of water, even although a certain amount of boiling takes place. Judging by our past experience, this certainly has been satisfactory, and a tower scheme on the radiator was adopted during the Austrian Trials in 1913. This tower scheme could not be adopted in the Spanish trials of the same year, as the authorities would not allow anything but a standard car. We are able, however, to overcome the serious loss of water in this case by fixing a separator scheme in the filler of the radiator Contd:- R.R. 296A (100) H.S. 11/5/10 (50) 10/11-20 D 2962 | ||