TM-9-2350-277-40&P Sustainment Maintenance Manual M113A3 M577A3 M1064A3 M1068A3 M58 Download
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Figure 5. Operational Check. TESTING RESTRICTION AND OVERHEAT THERMOSTATS NOTE Thermostat shown in fuel control valve is set to open at 70° F (21° C) and to close at 30° F (-1° C). If temperature is below 70° F (21° C), the heating element in fuel control valve can be energized during any operational cycle. 1. Turn the heater on and run it until the coolant is hot enough to make the heater cycle from high to low heat. Leave the heater alone, then take the temperature of the coolant. The temperature should be between 140° F (60° C) and 170° F (76° C). If coolant temperature is not within limits, replace restriction thermostat (WP 0027). 2. After testing the restriction thermostat, close circuit across terminal board terminals No. 4 and No. 5, to make the heater stay on high heat. Heat the coolant until the heater burning stops. Check the temperature of the coolant, it should be not less than 220° F (104° C) or more than 250° F (121° C). If the coolant temperature is not within these limits, replace the overheat thermostat (WP 0028). TM 9-2350-277-40&P 0025 0025‐6