CHEVROLET 2010 HHR - Manual (Page 327)

If no coolant is visible in the coolant recovery tank, add
coolant at the pressure cap as follows:
1. Remove the pressure
cap when the cooling
system, including
the pressure cap and
upper radiator hose, is
no longer hot.
Turn the pressure cap slowly counterclockwise. If
you hear a hiss, wait for that to stop. A hiss means
there is still some pressure left to be vented.
2. Then keep turning the pressure cap and remove it.
3. Add the proper DEX-COOL ® coolant mixture to
the coolant fill port, up to the base of the port.
See Engine Coolant on page 6-29 Engine Coolant
for more information about the proper coolant
mixture.
4. Rinse or wipe any spilled coolant from the engine
and the compartment.
5. Then fill the coolant recovery tank to the COLD
FILL (A) line.
6. Put the cap back on the coolant recovery tank, but
leave the pressure cap off.
7. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
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