Here you go, courtesy of Scotty:
how to
flush coolant.
remove the t stat, put the t stat housing back on, take the upper hose off the
radiator, then push it down to the ground to a bucket or let it fly.
get your garden hose out, put it in the rad turn it on, then fire up the car, let it run till clear water pumps out the top hose.
then turn the hose off, run the car till no more water comes out the upper hose. then turn it off.
put your t stat back in, with new gasket, the upper hose back on.
now take 1 gallon of full strength green
antifreeze, not the 50/50 crap. ( parts store cheap green is fine to use) dump the whole gallon in the
radiator, fire up the car, fill the rad with hose water till its full. top as needed till its ready to be bled of air. it will burp and take
coolant as the water in the block warms up the t stat opens up for a few seconds till cold
coolant hits it and it shuts again.
now to bleed the air out, let it idle rad cap off till the fans turn on, (when the fans are on the temp is over 195 deg, the t stat is wide open) then open the bleeder screw on top the t stat housing a few turns till a steady stream of
coolant comes out the hole, shut the screw, top off the rad. cap it.
done.
