Originally Posted by Odin

You need to get the front of the truck up high enough to make the radiators filler neck the highest point in the system. Optimally you'd want it higher than the heaters flow control valve located on the firewall. The Lisle NoSpill Funnel is a great tool for adding height and keeping coolant from going all over the place. I use it and still jack the front end up as high as I can.

Some trucks don't have the heaters temperature selection/flow control cable adjusted to allow the valve to fully open when the controller is slid into the hot position from inside the truck, this will make it harder to bleed. You might want to disconnect the cable and fully open the valve then readjust it after bleeding the system. Another thing that helps dispel trapped air is making sure the thermostat you're using has a jiggle valve in it or at least a 1/16 inch hole drilled in it for air to pass through.

Keep the heaters blower motor switched OFF and slide the temp switch to full hot.
From that point let it warm up without the cap on and watch for the coolant to start rushing by the filler neck. That means the thermostat is now at least partially open. Now keep the engine around 2500+ to keep the water flow up and keep adding coolant as needed.


Eventually it won't want to take in any more coolant and the thermostat will be fully open, it'll take a while to get there though. At this point most of the air is out but not all of it and what's trapped in there can still cause rough idle or idle surge issues. You don't want air pockets around the air idle control valve or the temperature sensor that tells the ECU the engine is at operating temperature.

After that I'll let it idle for a minute then snap the throttle open till the engine hits about 3500-4000 to create pressure surges in the system. This helps drive out air pockets that may be sitting up high or at sharp bends. Pushing on the hoses at the sharper bends while the rpm is high also helps. I repeat this several times before I'm done. It'll usually take me 30 minutes or more before I consider it job done on my truck.




Although it's normal to make sure the radiator cap is good so the system holds pressure some don't consider that the system also draws coolant in from the overflow bottle when it cools down.
Consider the hose that goes to the overflow bottle a vacuum hose. If it fits loosely at the radiator or overflow bottle or it has a crack/hole in it your system will be drawing in air whenever it cools down. Since the system wants to draw coolant in as it cools down ANY dampness around a hose filled with water is another area for air to get in while the system cools down. Follow all of your hoses and make sure there are no "Slight" leaks or you'll soon have enough trapped air to once again cause problems.

You just might find a new leak source now that the system is full of coolant and being asked to hold full pressure for extended periods. I like to reexamine All of the hose ends a couple times a week after a good bleeding. For F.I. don't forget the hoses that go to and from the idle air control valve.

Originally Posted by wyoming9

I have found the easy way to do this is to just put a flushing tee in the heater hose next to the heater valve.

Since at times I was draining coolant pretty often .

filling the system it pushes the air out the open cap coolant comes out done.

Put cap back on done.

It worked so good all my 22R series engines have them.