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).
Informational leaflet with fitting instructions for a Smith R.P. Adjustable Thermostat.
| Identifier | ExFiles\Box 156\1\ scan0034 | |
| Date | 9th January 1934 guessed | |
| SMITH R.P. ADJUSTABLE THERMOSTAT (British Patent No. 314840) Diagram Annotations (Left): Direction of flow. Cap Nut to be removed when Dashboard Thermometer is used. Thermostatic Spring Element. Special Fabric Seating. Temperature Adjustment & Full Open Knob. Diagram Annotations (Right): Branch piece Housing for Smith Dashboard Thermometer. Thermostatic Spring Element. Special Fabric Seating. Main Text: The average engine gives best results when the cooling water in the cylinder block is at a temperature of between 70° C. and 90° C., and if, for example, your engine operates best at 90° C., it is obvious that it should always be run at this temperature, and further, this correct running temperature should be obtained in a few minutes after starting up. To obtain this ideal, the Smith “R.P.” Adjustable Thermostat has been devised. It fits into the top hosepipe between the engine and the radiator. This is the best position, as the thermostatic element controlling the valve is in actual contact with the cylinder block water, and is therefore capable of responding to the slightest temperature variation. The temperature is controlled only in the cylinder block, ensuring a reserve of cool water in the radiator, and enabling the motorist to employ temperatures up to 90° C. (Boiling point, 100° C.) The unique feature of the Smith “ R.P.” Adjustable Thermostat is that, by the instant setting of a small dial, the driver can adjust his engine temperature to any point up to 90° C., thus ensuring correct temperature. The valve remains closed until the predetermined temperature is attained in the cylinder block (approximately 2 to 3 minutes). The temperature thereafter, under touring speeds, is constant within 3° C., even in the coldest weather. During exceptionally hot weather, or in mountainous country, the valve may be fully opened if required. It will be appreciated that the Smith “ R.P.” Thermostat actually controls the engine temperature, whereas the normal thermostat is merely a “warming-up” device. The Smith “ R.P.” Adjustable Thermostat has a fabric-edged valve, which absolutely eliminates any possibility of valve sticking or jambing due to foreign matter in the water. FITTING INSTRUCTIONS The valve should be closed during fitting operation. Fit Thermostat with thermometer branch in horizontal position. Not as illustrated. THERMO-SYPHON CIRCULATION Drain radiator. Remove rubber hose from between top of radiator and cylinder block. Cut hose into two lengths. Fit Smith “R.P.” Thermostat in the rubber hose as closely as possible to the cylinder block. Diagram Annotations: RADIATOR Circulation Pipe CYLINDER BLOCK Pump PUMP CIRCULATION In the case of pump circulation, it is necessary to connect a rubber circulation pipe between the branch-piece on the Smith “ R.P.” Thermostat and the bottom hosepipe as closely as possible to the suction side of the pump (see illustration). With the special cutter and connector this connection is made in two or three minutes without removing anything. The extra cost (5/-) for pump circulation includes the cutter, two connectors, and a length of special canvas-ply hose. SMITH “R.P.” CONNECTOR By a few turns of Milled Disc the Rubber Plug or Connector expands inside the pipe after insertion in hole bored by the cutter, ensuring permanent watertight joint. PRICE: THERMO-SYPHON TYPE G 509 - 28/6 PUMP TYPE G 508 - 33/6 Postage 9d. | ||