Downloaded from www.Manualslib.com manuals search engine 3. Stop the engine. Open the radiator drain valve to drain the coolant. (Drainage
may be speeded by removing the drain plugs in the block.)
4. Close the drain valve (install block drain plugs, if removed). Add water until
the system is filled and run the engine until the upper radiator hose is hot again.
5. Repeat steps 3 and 4 several times until the drained liquid is nearly colorless.
6. Drain the system and then close the radiator drain valve tightly. (Install block
drain plugs, if removed.)
7. Disconnect all hoses from the coolant recovery tank. Remove the tank and
pour out any fluid. Scrub and clean the inside of the tank with soap and water.
Flush it well with clean water,
then drain it. Reinstall the tank and hoses.
8. Add enough water and ethylene glycol antifreeze (meeting GM Specification
1899-M)to provide the required cooling, freezing, and corrosion protection. Use a solution that is at least 50 percent antifreeze, but no more than 70
percent antifreeze. Fill the radiator to the base of the filler neck and fill the
coolant recovery
tank to the "Full Hot" mark. Put the recovery tank cap back
on.
9. Run the engine, with the radiator cap removed, until the upper radiator hose
is hot.
10. With the engine idling, add coolant to the radiator until it reaches the bottom
of the filler neck. Install the radiator cap, making sure the arrows on the cap line up with the overflow. tube.
It is the owner's responsibility to:
• Maintain cooling system freeze protection at _37°C (_34°F) to ensure
protection against corrosion and loss of coolant from boiling. (A SO/50
mixture of water and ethylene glycol antifreeze will provide freeze protection
to ~ 37°C ore -34°P.) You should do this even if you don't expect freezing
temperatures.
• Add ethylene glycol base antifreeze that meets GM Specification 1899-M
when antifreeze
hasto be added because of coolant loss or for more protection
' against freezing at temperatures lower than _37°C (-·J4°P).
NOTICE: Do not use alcohol or methanol-base antifreeze. or plain water alone. in your vehicle at any time. They will boil at a lower pOint than that at which the hot light indicator (or temperature gage) works. and they do not provide proper protection against corrosion.
Radiator Pressure Cap
The radiator cap, a 105 kPa(15 psi) pressure type, must be installed tightly,
otherwise coolant may be lost and damage to engine may result from overheating.
Radiator pressure caps should be checked periodically for proper operation.
If
replacement is required, an AC cap is recommended.
Thermostat
The engine coolant temperature is controlled by a thermostat. It stops coolant flow
through the radiator until a preset temperature is reached. This thermostat is
installed in
the engine coolant outlet on the engine block. The same thermostat is used in both winter and summer. When a replacement is needed, AC~Delco parts
are recommended.
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