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).
Engine cooling improvements and boiling tests.
| Identifier | ExFiles\Box 38\2\ Scan239 | |
| Date | 11th September 1924 | |
| H.R. 493A (40 H) (SL 42 13-7-23). J.H.,D.{John DeLooze - Company Secretary} -4- EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}1/LG11.9.24. The tests are being continued. As far as we can see there are three ways in which improvement can be made as regards cooling. 1. Improving the efficiency of the fan and drive. 2. Improving the ventilation. (This will be a more noticeable improvement at high speeds rather than hill climbing). 3. Larger matrix. In all of the cases brought to our notice we have not heard of a case in which the boiling has caused any failure to the engine or that it has been likely to cause any failure. We have carried out tests on the road and have proved that we can run a 40/50 HP. or a 20 HP. car for 30 or 40 miles boiling, and still not affect the running of the car. We have run a 40/50 HP. car full power on the dynamometer at 1250 revs. for half-an-hour - no harm was done to the engine. We believe that the reason we only have a small percentage of complaints of boiling is because that most of the drivers on our cars realise that there is no harm caused by the water boiling and that there is no need to break the journey in order to fill up. Our cars running on the 4-wheel brake tests, were running during the hot weather round about boiling point for 250 miles but they never stopped to fill up with water until they had completed the run. The maximum amount of water lost was 3 gallons, there was still left 4 1/2 gallons approx. for circulation. There is difficulty in explaining to a customer contd:- | ||