You have to take the lower rad hose off. They stopped putting the drain valve on the systems after 2002.
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In a 2002 trailblazer it is located on the bottom of the radiator one the passenger side. Every other model year to my knowlege does not have drain plug.
Place something to catch the engine coolant beneath your 1990 Chevy Corsica radiator. Remove the radiator drain plug with a 9/16 ratchet. The engine coolant will drain out.
The radiator drain plug on a 2003 Chevrolet Trailblazer is typically located at the bottom of the radiator, on the passenger side. Look for a small plastic or metal petcock that can be turned to release coolant. Ensure the engine is cool before attempting to drain the radiator to avoid burns or injury.
Disconnect the lower coolant hose.
Look at the rear or bottom of the radiator
Remove the drain plug from the bottom of your 2002 Chevy Camaro radiator. Allow the coolant to drain out into a container. When all the coolant is drained out replace the drain plug to its original position. Fill the radiator with new coolant.
The radiator drain plug on a 2004 Chevy Venture is located at the bottom, left side of the radiator. It allows for the coolant to be quickly drained during maintenance.
To flush the coolant on a 2006 Chevy Equinox, first, ensure the engine is cool, then remove the radiator cap and place a drain pan underneath the radiator. Open the petcock at the bottom of the radiator to drain the old coolant completely. After draining, close the petcock, fill the radiator with a coolant flush solution and water, run the engine to circulate the solution, then drain it again. Finally, refill the radiator with the appropriate coolant mixture and check for leaks.
There should be a drain valve on the radiator on the bottom passengers side If not just undo the bottom radiator hose.
I assume you want to change out the water pump and would like to know if you can do it without draining the radiator. You will lose approximately all the coolant in the radiator reservoir when you remove the radiator hose from the water pump. If the coolant is in good, clean condition, it might be wise to drain the radiator into a container and re-use the coolant.
its there....i think its a screw on the very bottom of the radiator..faces the ground if you dont see one disconnect the lower radiator hose
To change the thermostat on a 2002 Chevy Trailblazer EXT, first, ensure the engine is cool and disconnect the negative battery cable. Drain the coolant from the radiator, then remove the thermostat housing by unscrewing the bolts. Replace the old thermostat with a new one, ensuring the gasket is in place, reattach the housing, and refill the radiator with coolant. Finally, reconnect the battery and start the engine, checking for leaks.