Chevrolet S10 Pickup 2003 Owner's Manual page 304

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX-COOL
through the filler neck until the level reaches
the base of the filler neck.
5-38
®
coolant mixture
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up like this.