Flushing A Closed Cooling System

[Slop]

Going to be doing this Monday morning on my 88, I have never done this on a closed system so I’m looking for any tricks or tips y’all may have that will make this project go smoothly

[ComancheKid45]

Pull the lower radiator hose to drain the system, Than if your gonna use a hose to flush the system just undo a hose or 2 at the Thermostat and run water through everything till it is clear from the other side. When youre done and ready to refill either jack up the truck as high as you can from the rear axle or back it up onto a slanted service. Crack open the coolant temp sensor on the back drivers corner of the engine and fill system untill coolant begins to flow from that area. Drop the truck down and Let engine reach operating temp. Then fill coolant bottle to spec.

[1989 Eliminator]

There is a drain fitting at the bottom left side of the radiator (facing the front of the truck). So I take off my grill, about 6 screws, then I put a small hose that fits the diameter of that drain C#*@ fitting. I feed the hose through the bottom of the truck so it dangles down. Then I place a container for the fluid to drain into. It takes a few turns for the fluid to start flowing (Make sure you do not screw it all the way out).

 

For a really good drain I actually start the truck while its still draining and keep filling the pressure bottle with a hose to have a continuous flow. I do this until the fluid becomes fairly clear. Then I let the hose water drain all the way and fill it back up with coolant.