Currently trying to remove my heater core (and box).

It's a 74 big block with AC.

Looks like I don't have the proper size wrench in my toolbox, so before I go find them, I'd like to make sure I'm going to remove the proper connections.

Based on the first picture below, I pointed out the 2 connections I'm planning on disconnecting from the VIR.

1) Is this correct? (Really don't want to touch a high pressure line from the AC.
2) The one with 2 arrows; is it a 2 wrench job like the fuel filter line?
3) Anyone knows the size of those?  The biggest wrench I have is 7/8 and it's too small.
4) The second pictures show the oil/grease build-up on the entire VIR and the oil line.  What would this usually indicate?

Pic 1


Pic 2


(modified LARGE images to links)
Adams' Apple2011-02-14 10:54:37

Pics were waaay too large, but I changed them to links, so they should work much mo betta now.

You do NOT have to remove any of that stuff to get the heater core OR the inside box/plenum out. All of the A/C stuff is on the engine side of the firewall, and the heater stuff is on the inside of the cabin.
If the A/C is working, and you remove ANY of the lines for the VIR, or anywhere else in the A/C system, you're gonna loose the freon....there's no other way around that, unless you have a recovery system....and I'm assuming you do not.

The grunge on the VIR could be engine oil leakage, or it could be A/C refrigerant oil leakage...hard to tell from the pics. Are you sure it's not some kind of undercoating?
Regardless of what it is, I wouldn't consider it "normal". Something is leaking onto/from the VIR.

Wrench sizes are gonna be in the 1 1/4" to 1 3/4" sizes...perhaps larger....it's been a while since I've done any A/C work on older GMs....
Adams' Apple2011-02-14 11:02:58

Wow; good thing I didn't have the correct size.... would have lost some pressure there!

I had the heater and A/C components mixed-up a little.  It's starting to make sense now.

I just had a very quick look and one of the radiator hoses on the passenger side (second down from the top below the bouchon) connects right back to the radiator near the bottom.  And on the passenger side, near "under" the blower motor area; there's always been a disconnected hose "looking up"; always thought it was some air intake or left over from the air pump that is no longer there.

I'm starting to think that the heater core has been bypassed entirely by looping at the radiator.  I'll raise the car tonight if I have time and take a look-see.

Steph.