My heater is doing it's job great...even when the switch is turned to cold it still blows hot air.
I will assume that there are some vacuum lines missing due to the 4.0 drivetrain swap that I need to install, as well as that little round valve thingy (water valve?) in the engine bay (mine is seized, had to use a wrench to open it). As of right now the thing is open all the time.
Should I find the vacuum lines and install them, then find a source for that valve (or similar from any other vehicle, doesn't matter to me), or do I have another issue?
http://amceaglesden.com/guide/File:Accontrolpanel.jpg
If your heater valve is in the open position for any reason (stuck open or no vacuum applied), you will get heat all the time. I believe the default position is open/heat, and vacuum is applied for A/C (assuming the valve is working freely).
In that diagram you posted, that blend air cable goes to the heater box and controls a flap that blocks off the heater core compartment when switched to cold. There is a lot of foam in that area that has probably disintegrated, or the cable didn't get adjusted right, and the flap isn't closing completely.
But I don't know how the A/C part works
The vacuum operates the heater valve. If it is froze like you said then you will be running hot coolant through your heater core all the time. Even so if all your control cables are still connected and your air flow doors are operating it should not be a big deal, but as said by Draekon, if the foam seals are gone or the doors are not moving ,then you will get hot air mixing with the cold and in the summer the heat wins out.
The valve is seized, I know that for a fact. I had to wrench the thing open for heat last winter. As for the door, I'll take a look-see and check what it's doing. If it's staying open that could be the problem.
Any place to source those valves? Or similar?
Edit : Eagle one is ridiculously expensive, but the Jeep version (which appears to be the same, just a bit different shaped) looks workable :
http://www.rockauto.com/catalog/moreinfo.php?pk=815449&cc=1180178&jnid=493&jpid=1
All the hose connections are 5/8 . The heater core has a 3/4 and a 5/8 . You will need to get some adaptors to hook it up but I think it would work. All though that would be a lot of hose clamps .
I just work the 5/8" hose onto the 3/4" fitting. Old hose will do it fairly easy but is more inclined to split.
Quote from: Nightpath on May 28, 2015, 12:40:43 PM
Edit : Eagle one is ridiculously expensive, but the Jeep version (which appears to be the same, just a bit different shaped) looks workable :
I'm not sure which Eagle heater valve you were looking at that was so expensive but when I look it up on RockAuto the cost is $7-11. Its a different style than the original as it doesn't have a bypass feature but that's the one I installed in mine and it works fine.
Are you certain the air mixer flap door cable actually moves the the flap above the passenger feet.
Quote from: vangremlin on May 28, 2015, 05:53:47 PM
Quote from: Nightpath on May 28, 2015, 12:40:43 PM
Edit : Eagle one is ridiculously expensive, but the Jeep version (which appears to be the same, just a bit different shaped) looks workable :
I'm not sure which Eagle heater valve you were looking at that was so expensive but when I look it up on RockAuto the cost is $7-11. Its a different style than the original as it doesn't have a bypass feature but that's the one I installed in mine and it works fine.
The valves I saw were $80-120. What model /year did you find the others under.
Universal ones are cheaper.
I looked under 1980. Its Four Seasons Part # 74612
I wasn't turning the switch down to Cold/AC...I was just moving the top slider lmfao. It blows cold(ish)...still though, might buy one of those things when I make an order.