Adding coolant

add to the overflow tank and then run the truck to get the air worked out. You'll probably have to add some more afterwards.

 

If you've got a rad with a cap on the top tank, pour it directly into the rad first then top off the overflow bottle.

 

Always check & top off cold/morning w/heater control to hot"...so it fills the hoses& heater ore.. It will eventually bleed the air out

 

You. Don't have fill cap? What the hell kind of engine you are running pray tell? ALL radiators with coolant have a fill somewhere.

As noted by others there is a alternate at the overflow tank. Keep feeding coolant into it as you run the engine. You need to make sure you feed coolant into it until the air quits escaping.

The next problem will be a pressure test to be sure you are at the correct pressure once you reach operating temp. And keep adding coolant until your system stabilizes.

You can tell if there is a fluid issue due to air in the block when the temp sensor starts to cause the temp reading needle to pulse. You will literally see it.

 

Even the newer trucks with no radiator cap, and have to be filled from the reservoir tank, have bleeder valves on the upper radiator hose. Just unscrew it, fill the reservoir until coolant starts coming out the valve, tighten it down and fill reservoir to max cold line. It is also a good idea to occasionally squeeze the flexible portion of the upper hose several times to help get any remaining air out of the top of the engine. Then go ahead and go to work. Just watch it over the next few days and add coolant as needed. I have seen mechanics that didn't know that is what the bleeder valve on top the upper radiator hose is for and had to explain it to them!