Refer to TB-750-651 (Use of Antifreeze, Cooling System).
Never add coolant to an overheated engine. Allow the engine to cool first.
Measure the specific gravity of antifreeze solution frequently in cold weather to ensure adequate
When permanent type antifreeze and water solutions are used in the cooling system, drain and replace
the solution EVERY 2000 SERVICE HOURS OR YEARLY. When additions of conditioner are made as
recommended, the drain and refill period can be extended to every 4000 service hours or every 2 years.
The cooling system should contain a 3% to 6% concentration of conditioner at all times, regardless of
the antifreeze concentration.
If the machine is shipped to, or stored in an area with freezing temperatures, the cooling system must
either be protected to the lowest expected temperature or drained completely.
Do not use Caterpillar Cooling System Conditioner with Dowtherm 209 coolant.
The engine cooling system is protected to -20° F(-28° C), with permanent type antifreeze, when shipped from the
Pure undiluted antifreeze will freeze at -10° F (-23° C).
Use clean water that is low in scale forming minerals--not softened water.
When refilling the cooling system, always check the coolant level when the engine reaches normal operating
Filling the cooling system at over a 5 gpm (I9 liters/min) rate can cause air pockets in the cooling system.
When measuring the coolant level inspect the filler cap gasket. Replace the gasket if it is damaged.
Premix antifreeze to provide protection to the lowest expected temperature.
Operate with a thermostat in the cooling system all year round. Cooling system problems can arise without a
If NBC exposure is suspected, all air filter media should be handled by personnel wearing protective
equipment. Consult your unit NBC Officer or NBC NCO for appropriate handling or disposal instruc-
ENGINE AIR CLEANER
Inspect the air cleaner precleaned daily for accumulation of dirt and debris.
Service the air cleaner when the red band is visible in the air cleaner indicator.