There should be a drainplug below the radiator, take off the filler cap and rinse whith water. heating on max!
Reinstall the drainplug, fill with clean water and dive 100 miles or so,( engine must be warm with cap on!) than start over again untill you drain clean water,
Fill it with new coolant. check the level after 30 miles.
I will wait for nice weather to do so!

 

Take to a shop and let them do it!

But still does not do a 100% flush; that requires removing freeze plugs...which is not fun to do with the engine in.

 

You do this with the engine running??

 

Only way to flush the cooling system is to remove the thermostat and run the engine so the water pump, pumps the flush solution throughout the engine.

Shut off engine, let cool for a few minutes, drain radiator. Now my method is to now start the engine and then slowly fill the radiator with water. I do this so as to not crack the block with the sudden addition of cold water.

Once full, run engine for a few minutes, then let cool down a bit, drain radiator and repeat until water drained from radiator is pretty clear.

Once all clear, then add the 50/50 coolant mix.

Like I said, messy, but not difficult. Disposing of the flush, coolant is the major problem. Do not want to dump that stuff on the ground and there is alot to catch in containers to take to a hazardous chemicals collection place.

 

Correct LannyL81,


but I leave the thermostat as it is, therefore you drive a while till it opens.
Repeat a few times and it is done.
Yes take care with cold water and a hot engine, fill verry slowly, or wait for cooling down!
Good Luck!!