[QUOTE=dsireme]Is this the valve everyone is talking about??? Adams' Apple2009-06-09 09:56:26

[QUOTE=aceinthehole][QUOTE=dsireme]Is this the valve everyone is talking about???  Not sure how well the plastic one works. I used the metal style, but you don't have to mess with the copper tubing. You could just buy the screw in hose barbs, and use a little teflon tape to seal the threads. [/QUOTE] Adams' Apple2009-06-09 09:58:32

[QUOTE=dsireme]And Joel, what is this tying hoses together, is the like having your tubes tied??? [/QUOTE]

Well...I wouldn't know...my tubes have never been tied...(that I'm aware of...)

What I am referring to is removing the hoses from the heater core, and installing a short piece of metal tubing to connect the two hoses(from the engine) together. It's like taking two hoses to make one...does that help?
Adams' Apple2009-06-09 10:04:00

[QUOTE=Adams' Apple] [QUOTE=dsireme]And Joel, what is this tying hoses together, is the like having your tubes tied??? [/QUOTE]

Well...I wouldn't know...my tubes have never been tied...(that I'm aware of...)

What I am referring to is removing the hoses from the heater core, and installing a short piece of metal tubing to connect the two hoses(from the engine) together. It's like taking two hoses to make one...does that help?
[/QUOTE]

[QUOTE=dsireme] Screw in what?(no comment some of you) I have no clue what that is.[/QUOTE]

The piece I used 20 years ago on my Grand Prix was a U-shaped metal tube.  I'll check out the plumbing area of my local Home Depot and see if I can find anything with two different sizes on either end.

If you are going to install only one valve you would install a valve in THIS hose where Im pointing.   If you are going to install two valves, the second one would go on the hose which exits the heater core and goes to the water pump HERE.  If you prefer the valves not to show, they can be installed under the car but still in reach without lifting the car LIKE THIS.  These valves are under the car near the heater core inlets where the hoses turn upward to connect to the core.  The valves you see are the NAPA valves.

My heater core has been bypassed by  hose, the bad part is I don't see where the hoses should hook to the heater core. I LIKE a heater in the winter even here in the south.So, I'm having vacuum line problems with my A/C-the A/C  blows nice and cold below the dash but the vacuum lines that operate the ducts are not there so I'll be tracing and replacing them but at the same time I would really like to know where my heater core is! On most GMs it's in the fiberglass box that is by the A/C dryer, but I see no tubes sticking out there...help anyone?

How come mo one makes sure the valve installed into the car is working. The valve installed is operated by vacum from a vacum switch behind the passenger dash panel and is acuated by the temp selector being moved to the off position. (1977) not shure the different year changes but should be similiar. If operation is correct the water is shutoff. then as to Joels point you would want to add the valve on the return side to stop the convection off heat from that hose. which if we were to install another vacum valve on this hose and tee it off, it should block all heat and work automaticly no mechanical valvesneeded?

[QUOTE=mysticstriper]My heater core has been bypassed by  hose, the bad part is I don't see where the hoses should hook to the heater core. I LIKE a heater in the winter even here in the south.So, I'm having vacuum line problems with my A/C-the A/C  blows nice and cold below the dash but the vacuum lines that operate the ducts are not there so I'll be tracing and replacing them but at the same time I would really like to know where my heater core is! On most GMs it's in the fiberglass box that is by the A/C dryer, but I see no tubes sticking out there...help anyone?[/QUOTE] The tubes are on the bottom, need to get under the car to get to them.