TM-9-2350-358-BD M109A6 Battlefield Damage Assessment and Repair Download

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TM 9-2350-358-BD 6-6. COOLANT SUBSTITUTE General Information: During performance of repairs or as a result of leakage the coolant may become lost. A liquid cooled engine cannot operate for long without coolant. When normal coolants are not available, a substitute may be used. Any liquid, except gasoline or jet fuels, can be used as a substitute but some liquids will deteriorate the cooling system rubber components. Petroleum products will not transfer the heat as efficiently as a water-based coolant, but will work if nothing else is available. Old engine oil or fluids drained from damaged vehicles, transmission oil, hydraulic systems, may be a possible source of fluids. The cooling system must be drained as soon as possible if petroleum-based fluids are used. Limitations: None Personnel/Time Required: 1 soldier 1.0 hour Materials/Tools: 14.5 gallons of liquid References: TM 9-2350-314-10 TM 9-2350-314-20-1-1 Procedural Steps: 1. Repair cause of liquid loss. 2. Fill cooling system with liquid. 3. Record the BDAR action taken. When mission is complete, as soon as practical, repair the equipment/system using standard maintenance procedures. 6-7. THERMOSTAT STUCK General Information: The thermostat regulates the engine operating temperature, from 180 to 195 degrees F, by controlling coolant flow through the engine. When the thermostat is stuck in the closed position it prevents coolant from circulating and causes engine overheating. BDAR repair is to remove the thermostat and operate the vehicle. If the thermostat is stuck in the open position or removed, it may degrade engine performance and increase fuel consumption. Limitations: None 6-6