LINK ASSEM. 1V7077 - Caterpillar

Check the coolant level when the engine is stopped and cool.
Pressurized System: Hot coolant can cause serious burns. To open the cooling system filler cap, stop the engine and wait until the cooling system components are cool. Loosen the cooling system pressure cap slowly in order to relieve the pressure.
Remove the cooling system filler cap slowly to relieve pressure.
Maintain the coolant level within 13 mm (0.5 inch) of the bottom of the filler pipe. If the engine is equipped with a sight glass, maintain the coolant level to the proper level in the sight glass.
Illustration 1 g00103639
Typical filler cap gaskets
Clean the cooling system filler cap and inspect the condition of the filler cap gaskets. Replace the cooling system filler cap if the filler cap gaskets are damaged. Reinstall the cooling system filler cap.
Inspect the cooling system for leaks.
Illustration 2 g06205388
(4) ( 6) separate circuit aftercooler (SCAC) drain valve
(5) jacket water heater drain valve
Remove the vent cap, and fill separate circuit aftercooler from the SCAC drain valve (5).
Fill the jacket water heater from the jacket water heater drain valve on the floor (6).
Fill to the high level mark on the shunt tank sight glass indicator.