caseysrex

Ok so i have searched iclub and really cant find anything that answers my question. i have a 2003 wrx and was wondering which radiator cap i take off and which hose i use to drain the coolant? do i use both plugs to drain or if i just use the one attached to the radiator will that drain out everything? is there even two plugs haha? and when i go to fill the radiator do I just use the cap on top of the radiator and leave the one by the turbo alone? any comments would help out a ton. i guess i just dont understand the two caps. kind of a noob question but any help would help out. thanks a ton

Keisatsu

I have an '02 rex so it didn't come with the cap ON the radiator just the fill tank by the turbo...

So I'm pretty sure you'd be fine using that one.

As for the drain I used the one on the passenger side bottom of the radiator...

When in doubt check the owners manual.

peace
-jacob

Mulder

If you have an 03 with a cap on the radiator, then the radiator must have been replaced at some point. The updated radiator with a cap was introduced during the 04 model year, it was redesigned to reduce the incidence of leakage from the tanks and the cap added to help with the problem of trapped air during cooling system service. The second cap makes draining and refilling the system much easier.
You can find information on cooling system service here-
http://forums.nasioc.com/forums/showthread.php?t=504002
You'd need to follow the procedure for the 04-later rather than the original procedure for your 03.

caseysrex

So what you are saying is to just leave the radiator cap alone that is by the turbo and just use the one that is on the radiator and that fill tank? is that right? and thanks a ton for the quick replys. that guide should help out a lot. but i still am confused about this one question.

Mulder

Well I have the same setup on my 02 (upgraded to the 04 radiator w/cap). When I've drained/refilled the coolant I removed both caps. You can fill through the small tank by the turbo, having the rad cap open allows air to escape instead of being trapped like it would be with the older radiator. If necessary you can add coolant through the radiator as well to bring it to the top, when you're done the coolant should come up to the bottom of both filler necks. If you keep track of how much you are putting in you'll have an idea whether it's truly full or if there's any air.
Be sure to add the coolant slowly, this allows air to escape more readily. Don't add it all at once, pause a few times to let it settle and you'll see some bubbles as the air comes out.
When you're done filling the system then put some in the recovery bottle. After the engine has been run and allowed to cool a few times you may have to readjust the level.
I've done mine a couple of times and have had no problems whatsoever with trapped air.

caseysrex

hey thanks!! ok that helps out a ton! thanks for the replys everyone!