Changing Coolant on 7.3 idi

[BigDogIDI]

So.... I need to change my coolant. Long story short: I am no longer at a 50/50 mixture. I have the proper sca coolant I need. But, how do I completely drain ALL the coolant from my radiator, block, etc?

 

[Thewespaul]

You will need to remove the block drain plugs, it’s a common upgrade to put a petcock there

 

[IDIBRONCO]

To get a little bit more to drain out, I'd disconnect one of the heater hoses at the engine (doesn't matter which one) and blow through the heater core to remove the coolant from there. If you use compressed air for this, remember that the cooling system sees less than 20 PSI so be careful. I just use my mouth when I do this. I don't build anywhere near 20 PSI.

 

[BigDogIDI]

Thanks. Where are the block drain plugs?

 

[IDIBRONCO]

There's one on each side down towards the oil pan. They're made of brass. They take a 9/16 socket to loosen them. Be careful. It's easy take a green shower when removing them!