Heater core control - hoses in engine compartment (UPDATE)

[FSHTAIL]

I have a 73 Cuda...
Since I've owned it, it had the heater core hoses from the engine going directly to the firewall to the heater core.. 

Is this correct?

In the summertime, it feels like the heat is on, but it's all turned off (non a/c car)   

I always thought it was due to the headers.. 

What am I missing?       Or is this how it is?

Thanks

[73_Cuda_4_Me]

Unfortunately, it's correct... There is no valve to cut the flow off on a non-AC unit on a 73 Cuda.

It's really noticeable when the foam gasket on the 'blend' door deteriorates and can leak, so that the air can flow through the core into the cabin.

One solution is to add a manual 1/4-turn shut-off valve to one of the hoses to stop the flow during the summer... but that removes the option to run the heater to help cool the engine on really hot days that some people have had to use once in a while... (don't ask me how I know).

[FSHTAIL]

Unfortunately, it's correct... There is no valve to cut the flow off on a non-AC unit on a 73 Cuda.

It's really noticeable when the foam gasket on the 'blend' door deteriorates and can leak, so that the air can flow through the core into the cabin.

One solution is to add a manual 1/4-turn shut-off valve to one of the hoses to stop the flow during the summer... but that removes the option to run the heater to help cool the engine on really hot days that some people have had to use once in a while... (don't ask me how I know).

I'll add an inline ball valve, I think the upper hose is a 5/8" and it's the inlet?    Or is the 1/2" hose the inlet?
Would I need to do anything to the other hose or just stop up the inlet only?   

[Dakota]

You'd be good on one valve as long as you're not worried about the heater core leaking. One valve is all  that's on mine. 

[FSHTAIL]

You'd be good on one valve as long as you're not worried about the heater core leaking. One valve is all  that's on mine.

Leaking?

Did you do yours on the upper hose?   
Is the upper the inlet?

I figured I'd crack it open now and then to keep it from gelling up..   

[Dakota]

My car is a 70 Challenger with A/C, but the heater control valve is for 71-74 (soundcontrol is dealing with the 70 version).   According to the service manual, the inlet for the Challenger heater is on the left as you face the firewall from the engine side.   It is the larger diameter line (5/8" if I recall correctly).

There's a picture of the 71-74 valve below.  It has connections for both the inlet and  outlet lines, but the inlet side (lower tube) is just a pass-thru.  The "butterfly" plate for the valve is only in the outlet tube.  Again, this is for an A/C equipped heater box.

That's a lot of words to say that one valve is all you need.   If you had a leaking heater core, you'd need valves on both the inlet and outlet lines to isolate it, or you could just tie the inlet and outlet lines together and bypass the heater core entirely.

[Burdar]

There's no reason why you couldn't add the A/C valve to your car.  Then you could use a universal choke cable to activate it.  That way you'd have control over it from inside the car.

[RUNCHARGER]

72-80 Dodge pickups had an inline water control valve. Probably easy to find.

[FSHTAIL]

UPDATE

because I forgot till now...
simplicity, quarter turn valve with a rust proof coating found here.. 

I'll crack it open from time to time while its warming up to circulate the heater core..

It doesn't stand out...   simple...

https://www.ebay.com/itm/392430369845?hash=item5b5eac3c35:g:dL8AAOSwELRdgFbM

take care

[Purepony]

Any update on how this is working out ?

Did it solve your problem with the heater feeling on ? I'm going to be doing the same since mine also feels like the heaters always on

[FSHTAIL]

It solved all my issues..   

No heat in the cockpit unless I want it there with a 1/4 turn of the valve.   

Any update on how this is working out ?

Did it solve your problem with the heater feeling on ? I'm going to be doing the same since mine also feels like the heaters always on

[Purepony]

Thanks for sharing I'm going to get one