Heaterbox weirdness

[twodko]

Good morning (afternoon/evening) gang,
I hope I can explain this clearly. Yesterday was clear, sunny but cold here in NorCal so we took the Charger out for a cruise. What a day it was to drive. Car is running well and received quite a few  .
I mentioned a few weeks back that we were getting cold air blowing in on the passenger side floor area. All the vents were closed and all of ther heater controls were closed. The first ugly thing that came to mind was perhaps the plenum gasket had an edge that folded over when I put the box back in. Were this to be the case, would cold air freely blow into the car? I checked the cable at the lower vent and it opens a closes the flapper inside as its supposed to.
While we were out I tested all of the heater controls (ours is a non AC car). Fan switch functions normally. Off-Heat-Defrost control directs the airflow properly. On the other hand, the "heat" control seems to be either on or off, heat or cold. It would appear there is no cold air coming in to vary the heat output. I am so frustrated. The car is freshly painted, painstakingly reassembled and the prospect of pulling out the passenger seat, console and brand new glove box to see what's going on is not a pleasant thought. Does it matter which heater hose I put on the core tubes? I don't see how that would make a difference.....its just a flow through system right? The only other cables I can't check for proper operation are the ones behind the radio etc.
I took many photos during the heater box disassembly to assure I put it back together correctly. During reassembly no internal parts were bent, deformed, cracked or otherwise damaged and I used DMT's gasket set closely following the instructions. I don't see how it would be possible to incorrectly reinstall any of the flappers because they only work one way (I think). My first inclination is to pull the radio out to access the 2 heater control cables behind and see if there is an obvious issue.  What should be the order of diagnostic steps to narrow this problem down? I know its hard to tell what the issue might be if you aren't physically here to check it out. I'd like to troubleshoot this thingy smartly instead of chasing gremlins. Any thoughts guys? Does anything stand out as a probable culprit?

[el dub]

Did you replace the heater control valve?

[twodko]

Do you have a pix of this valve? Where would it be located? There wasn't any heater control valve in or around the heater box when I removed and rebuilt the box. The car is a non-AC car so there isn't anything bolted to the engine bay firewall. Just the 2 holes for the hoses. 

[el dub]

I tried to download but it's to big. I can email it though.

[twodko]

That would be great! I tried a search here on the forum for anything under "heater control valve" and came up with zero. I'm sure curious about it now. We bought this car from the OO and it had never been touched so "parts being left out" at some point doesn't apply. Anyway I'll watch for the pix. 

[FLG]

The heater control valve sits right before your heater core in your engine bay, I'm not sure if it differes or what not but its most likely controlled by a wire running from your heater controls when you slide from warm to cold you physically open and close this valve. The valve allows the hot engine coolant to circulate through your heater core (I do believe some cars have this valve vac operated but I'm thinking its ac cars that do) if this is not there or not operational and in the open position, you will always have heat. If its not there you could get a replacement (on mt phone right now so bit difficult for me to find things but I'm pretty sure they're making em new) if its there you just need to ensure its operation. Again I'm not sure on 2nd gens if its vacc or controlled by a wire (not electrical but phsyical) which open and closes it as you move the warm-cool slider.

[FLG]

Here ya go

http://www.vapinc.com/mopar/Heater%20Valves/main.html


There's plenty of threads, make sure when you use the search function your on the main forum page, the "home" page, or you click the little magnifing glasse next to the search bar and use the advanced search. Otherwise it will only search the thread your in, or the topic your in (for example if your in the engine forum and you do a search it will only look throuh that topic and not the others) or if your veiwing a thread when you do a search it will only search that particular thread.

[twodko]

Frank thanks for the "search" tips. The valve you guys are referecing must be specific to 3rd gens. My 2nd gen non AC car doesn't have one. Maybe the AC cars do but my car has a basic heat/defrost box.

[el dub]

The cable, or wire that goes to your heater knob may have a bend in it, even though the knob moves the cable doesnt

[FLG]

Frank thanks for the "search" tips. The valve you guys are referecing must be specific to 3rd gens. My 2nd gen non AC car doesn't have one. Maybe the AC cars do but my car has a basic heat/defrost box.

Every car came with one, hear or ac cars dosnt matter. If you don't have one you will always have hot fluid circulating through the heater core and will always have heat. If you don't have one your gonna need to get one to be able to use your cool - warm selection and will also need the cable that runs from the switch to the heater valve.

[twodko]

Hey Frank,

Well that would certainly explain why the heat control provides either nothing or heat but no mix. I just emailed my buddy from whom I bought the car, he's the OO. The core had a leak a some point so he took the core out of service and looped a section of heater hose to close the circuit. I'm thinking he forgot about this valve. I hope he remembers how it was controlled. If not "the forum knows all" and I'll be hitting the gang up for pix! I'm curious about what he'll have to say not to mention whether it was cable controlled or vac.

And here I thought I was done 

[FLG]

Tom I may have made a mistake...I did some reading and I think your correct...there is none on a non ac car. After some reading either you blend door seals are messed up or you need to adjust the cable that goes to the blend door. My apologies.

[twodko]

No worries Frank. I got out my FSM shorty after my last post to you and discovered the same thing. The blend flapper is exactly what meters the outside air through the intake plenum. It was getting late so I didn't dig out all the "before/after" pix I took when I resto'd the box. I do recall that the blend flapper only went in one way and I used DMT's gasket kit following their reassembly procedures. After checking the plenum gasket the cables will be next. I was reading the threads about unique speaker placement so I'm going to pull the vent grille off and I should be able to reach up there and feel the plenum gasket. If it is folded over that would explain why we get outside air in the cabin even when the vent controls are fully pushed in. Further, it would make sense that the heater/defroster wouldn't be able to blend properly because the system isn't getting the full outside air intake it needs to function.
The upside is I have a couple months before the car show season starts to get this worked out. Anyway, thanks buddy!