There is a kit made by Prestone and is sold at your local parts store. It is installed in the heater hose and uses water pressure to flush. The only other way I know is with a coolant flush machine.(Tool at a service garage). To check the radiator, use a non-touch type thermometer and test across at different heights looking for a cold spot. Also make sure there is no debri between the A/C condensor and the radiator. This can also make it look like a restricted radiator. Hope this helps, if you need more info., text me back. Good luck.
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There is a kit made by Prestone and is sold at your local parts store. It is installed in the heater hose and uses water pressure to flush. The only other way I know is with a coolant flush machine.(Tool at a service garage). To check the radiator, use a non-touch type thermometer and test across at different heights looking for a cold spot. Also make sure there is no debri between the A/C condensor and the radiator. This can also make it look like a restricted radiator. Hope this helps, if you need more info., text me back. Good luck.
(With the engine cold) remove the radiator cap
First drain the coolant out of the radiator in a container, either from a drain on the bottom of the rad, or by slowly removing the bottom rad hose.
Block, or pinch the top radiator hose
First, flush from the top... pour water into the rad cap hole for a while and let it come out the bottom hose.
Then, run water from the bottom, and let it run out of the open cap.
Then flush it from the top again.
This should flush the rad, unless it is clogged pretty solid.