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).
Guide to diagnosing and testing overheating issues in Phantom III cars.
| Identifier | ExFiles\Box 131\5\ scan0068 | |
| Date | 26th April 1938 | |
| RM{William Robotham - Chief Engineer}/Std.9/MR.26.4.38. OVER-HEATING - PH.III CARS. Over-heating troubles on Ph.III can be attributed to various causes - as per following list: (1) Matrix silted up - on a series cars with old type Mk.V matrix, approx. 150 in service likely to give trouble. (See RM{William Robotham - Chief Engineer}/Std.9/MR.23.4.38). (2) Idling over-heating in traffic - due to ineffective fan - applies to all cars. (3) Water pump failure due to loose solder causing pump rotor to shear. (4) Failure of water circulation due to splines on pump shaft wearing away. (5) Shortage of water due to steam valve not seating correctly. Before any work is done on an over-heating complaint it must be ascertained which of the above is causing the trouble- items (3), (4) and (5) can be checked by observation with filler cap removed. Items (1) can be checked by running car at high touring speeds on the road and observing water temperature. Item (2) is then arrived at by a process of elimination. Checking tests should, of course, be done with shutters fixed full open. The critical air temperature of the standard P.III car with bonnet shutters open is approx. 12°C, but when idled with car stationary, the engine can be run for approx. 24 minutes before reaching 100° or 33 minutes before reaching 105° (temperature for water loss with steam valve operating) on a day with atmospheric temperature of 18°C (or 64°F) starting from normal running temperature of engine. In this respect it is little worse than the standard Bentley car which will also boil if idled continuously on a day with average air temperature - 65°F say. | ||