Posted on April 5, 2021 3406E and 3456 Industrial Engines Testing and Adjusting – Water Temperature Regulator – Test Introduction This procedure is intended to give information on testing the water temperature regulator. Test Procedure Remove the water temperature regulator from the engine. Heat water in a pan until the temperature of the water is equal to the fully open temperature of the water temperature regulator. Refer to Specifications, “Water Temperature Regulator” for the fully open temperature of the water temperature regulator. Stir the water in the pan. This will distribute the temperature throughout the pan. Hang the water temperature regulator in the pan of water. The water temperature regulator must be below the surface of the water. The water temperature regulator must be away from the sides and the bottom of the pan. Keep the water at the correct temperature for ten minutes. After ten minutes, remove the water temperature regulator. Immediately measure the opening of the water temperature regulator. Refer to Specifications, “Water Temperature Regulator” for the minimum opening distance of the water temperature regulator at the fully open temperature. If the distance is less than the amount listed in the manual, replace the water temperature regulator.