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).
Issues found with the petrol, carburettor, and cooling systems during testing.
| Identifier | ExFiles\Box 125\1\ scan0206 | |
| Date | 5th March 1935 | |
| -5- PETROL SYSTEM. The petrol supply to the carburetters is by a mechanical pump situated on the near side front of the engine and driven from the driving chain for the timing gears. We had no trouble with the supply throughout the mileage. The pump has the glass container for the filter but apparently being placed well in front of the car is not affected by heat. We noted on several occasions that it was half full of water, and emptied same. We emptied the rear tank twice to get rid of any water that apparently was in the tank, but upon each occasion we failed to drain any water. We are anxious to see when the tank is dismantled whether there is a well in the tank that cannot be drained where the supply pipe is fitted. CARBURETTERS. We had further trouble with water and dirt entering the floats of the carburetters during the latter mileage. This, as previously reported, is due to the cheap pressing of the float chamber cover not making a joint. The thermostatic operation of the choke in the throats of the carburetters worked satisfactorily, starting from cold there was no hesitation in getting away. The choke flaps opened up after a few minutes' running. There was no petrol draining out after starting up. COOLING SYSTEM. The radiator was efficient, an average water temperature of 78°C. was maintained. The water level was kept fairly constant, not more than a pint being lost during a day's run. We had on two occasions a temporary sticking of the shutters which caused the water to boil for a few moments before the shutters freed themselves. With the massive grille and shell of the radiator it is impossible to see or get at the shutters. The coupling of the water pump drive rattled early on in the test. This consists of fibre blocks in a housing which, becoming slightly worn, rattle. A bad water leak developed during the last 200 miles, from a core plug on the near side block of cylinders. The plug is a disc, dished, and then pressed into position. The cause of the leak was apparently due to pressure in the system, as it did not occur until the car ran into a snow drift which closed up the ventilating pipe of the radiator. The plug, evidently being on the weak side, failed with extra pressure. The fan blades were damaged | ||