How do I fill the radiator 2004 v-10

[expo]

I'm doing my own coolant replacement and I can't find a radiator cap or any other way to fill the radiator.

Any suggestions on how I can accomplish this?

[jcthorne]

The coolant fill cap is on the expansion tank.

[expo]

Thanks for responding JC.

My experiences with expansion tanks are that they are siphon devices to keep the radiator topped off and don't directly fill the radiator. By pouring coolant into it, doesn't it require the heating and cooling of the system to pull from it on each cooling cycle?

I only see a 3/8" (or so) hose going to the radiator from the expansion tank, which would be pretty inefficient to fill it with. It seems, even if I were able to pump coolant through this line, I would still need to create an air vent somewhere to allow the radiator to fill without pressurizing it.

[Wanabee FTer]

If the upper radiator hose is easily accessible, you could remove it and use a flex tube funnel to fill the radiator, reconnect hose and top off the expansion tank. Then watch and adjust the levels after a couple of temp cycles.

John

[jcthorne]

The coolant expansion tanks on most Fords since the early 90s are part of the pressureized side of the system with a small part of the flow going through the tank. They are ususally placed so as to be the high point of the system. The pressure cap is ON the expansion tank. Its not an overflow bottle. The newer design prevents evaporative loses and dirty stagnent coolant in the bottle.

[koda59]

When I did my antifreeze change I just poored it in the expansion tank and it drained into the radiator. After you start up the rv make sure you have the heater set to full hot and the expantion tank cap off. This will help to remove any trapped air.

[expo]

Thanks for everybody's help on bringing me up to date on modern mechanics. I'm going for it the next time it gets over 60 here in OHIO