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Installing Classic Auto Air in a '70 Charger

My Mom said I was the bestest looking boy in school.

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UPDATE.
The cold air blew fine for awhile but doesn’t anymore. I’m not sure where the blame lies.
I drove the car to the Spring Fling 22 and it worked great…then about a month later the camshaft lost a few lobes so I pulled the engine to go through it. I left the compressor connected and thought I was careful. It took awhile to get the engine back in and when I did, we were closing in on Winter. By spring 23, I tried the A/C and got warm air. I busied myself with home repairs (and falling off the roof) so I didn’t make time to address the issue.
I’m doing a Vintage Air installation in a FBBO member’s car and want to avoid any mistakes that I may have done to my own car.
Did my system quit working because of bad crimps?

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Could it be a loose fitting? Bad O-ring somewhere?
A buddy gave me this thing a few years ago.

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He used it on my truck when it was blowing warm air. He put it on the fitting for what he called the “low side “ and the truck was in the white zone as shown on the gauge.

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I just tried it on my car.

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Okay, so it did have some pressure to it. I emptied the can into it and it topped out at around 32 psi, on the low side of the “Filled” range.

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Oddly, even with the higher pressure, the air still blows room temperature.
Another weird thing…the compressor clutch stays engaged whether the temp slide button is set to heat or cold.
Bad compressor?
I guess a test of pressure on the high side would tell, right? If the pressure there is the same, the compressor could be freewheeling, huh?
When I had the system charged in early April 2022, I went to a guy that owns a respected BMW shop because his wife has been cutting my hair since 1993.
I know…Great qualifications!
Actually, the guy has helped me with a few late model things over the years so I trusted him.
He didn’t run the system under a vacuum as long as I’ve read is recommended.

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I asked him if the 15 minutes was enough and he said “We do this all the time” so I reluctantly went along with it.
Other things on the list though:

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How about rule #1?

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He had the car running.
It worked after he was done and since he didn’t charge me, I was grateful and left there happy.
I am not happy anymore.

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I won’t take Dwayne’s car there.
Now I have to determine what is wrong so I can have cool air when I want it.
Oh… the heater works but isn’t as warm as my truck or the other newer cars here. It has never been as hot as I’d hoped.
CAA does state in their instructions the Importance of the water valve placement.

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Great. The lower heater core tube:


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What big block has a heater hose fitting on the intake? (None)

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That one I was able to follow.
 
It is hard to tell by the picture but…

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The hose nearest the belts is closest to the water pump itself and it has the water valve in it. The second hose in the picture is closer to the block. This is where the tech guy at CAA said to connect. There is no other water port on these engines so I wonder how two ports so close together can be much different in water temperature.
 
First trying to get an idea of state of charge when the ambient temp is below 60 degrees is kinda a waste of time... Second reading low side without the high side reading is a serious guessing game...

Try some soapy water on the charge ports and the various connections... The fact there's still some charge means it's a small leak, visual clues would be an oily film near a connection

Most systems have black light/UV dye, green residue in the low side charge port would be a sure sign.... Auto Zone will loan you a black light...

I assume you've put a wrench on all the fittings?

Both water hose connections are hot, but one is on the discharge side of the pump and the other is on the low pressure side....
 
During the installation, I made sure all the connections were tight but I'm not sure that I checked them after pulling and reinstalling the engine in late 2022. I have seen no evidence of leaks at the fittings but I'll look closer.
I was surprised to see the compressor clutch stay engaged even with the slide set to heat. It did not cycle off and on and was still ON when I restarted the engine a few minutes later.
I was told that the high side is some crazy high pressure, well above what the gauge on this unit has.

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Yeah, don't hook that to the high side... Sending high side pressure to that can could cause it to explode in your hand... Likely either your binary switch has failed closed or the clutch is stuck on without a signal.... Does the clutch disengage when unplugged?
 
Another weird thing…the compressor clutch stays engaged whether the temp slide button is set to heat or cold.
Bad compressor?
No. This is the way the system is designed and is supposed to operate. The compressor removes humidity, so when you are defrosting, having the compressor on while doing so helps keep the windshield clear.
 
That is how it works in my later model cars when the A/C button is pressed regardless of the temp position. The Classic system doesn't have a separate button for A/C, just this temperature slide knob.

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If I'm doing it wrong, I'm willing to learn!
 
That is how it works in my later model cars when the A/C button is pressed regardless of the temp position. The Classic system doesn't have a separate button for A/C, just this temperature slide knob.

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If I'm doing it wrong, I'm willing to learn!
I understand.

But my recollection of the way the Classic Air system works is that it always puts the compressor on - no A/C button to push. When the system turns on it always runs the compressor. All the sliders do is change the fan speed, the temperature of the air and where it blows.

I don't have the time now to dig up my instructions or search for the Classic Air specifications, but I am pretty sure of my response (although I have been wrong maybe once or twice! :poke: )
 
I purchased the Classic Air system for my 70 Roadrunner, non-factory air kit. I've since found a 70 correct factory air dash frame and a/c registers. I understand I won't be using an original center vent as Classic Air uses its own assembly so I just purchased the adapters for original side vents and a center vent, but now have some questions about how the center vent connects to the CA parts. My salesman said I have to have the original plenum that connects behind the center vent, possibly a metal ring that holds the center vent to the dash frame or plenum (not sure). The instructions are no help as it refers to a Figure 20, but the instructions go from Figure 19 right to figure 21, ugh. Can you tell me 1) what parts did you reuse from the original parts since yours was an A/C car and 2) how the center vent connects to the CA system? Thanks in advance for any help you can offer because Classic Air technical support was ZERO help.

Thanks,
Jim
 
I'll have to go back a bit and look but from memory:
I do remember that the lower panel in Factory A/C cars here:


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....came with a new screen/grid/grille for the center. That came with some type on non stock style collar that the new ducts attached to.


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do
I've had this car since March of 2000 and none of the heating nor A/C has ever worked in it. The car was originally an XP model Charger 500 with a 318 2 barrel, 904 automatic, 8 1/4" axle with 2.71 gears and 4 wheel 10" drum brakes. I had plans for a 440 so I kept the 318 totally intact and sold it a few weeks after the 440 was in and running. The car has not had an A/C compressor under the hood since 2001.
I always thought...Air Conditioning is for wimps....Hot rods don't need it.
Uhh....
After a few more birthdays, a few rides in other classics with A/C and several years of driving late model cars in DRY SHIRT comfort in 100 degree weather, I am convinced that A/C makes sense for me.
Some had suggested a rebuild of my stock under dash unit. I don't know much about these except that they are a mix of vacuum and electric in function and weigh a bunch. I had everything under the dash intact...ducts, hoses for the defroster, wiring uncut, everything was there but the vacuum controls worried me a bit. Leaks, low vacuum from a performance cam and the complexity drove me away from sticking with the stock stuff. I knew that I wanted a less cluttered underhood appearance than the original A/C cars had so I looked around at the vendors. Dennis H suggested Classic Auto Air so I checked them out.
I was impressed with the many options they offered for my car. They can build a kit to restore it to completely stock specs for an original A/C car, they can retrofit a "heater only" car to A/C....OR custom fit a series of parts to do a mix of the two.
I ordered the kit in February 2018. Yeah...It has been on the back burner for quite awhile.
One of the things that I wanted at first was to avoid the cluttered look of the stock 4 belt arrangement on the front of the engine. I worked to try to get a 3 belt setup to work, eliminating the idler pulley that the factory used.
you happen to have any photos of how the OEM right side cowl vent attaches to the cowl and heater box? hanks
 
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you happen to have any photos of how the OEM right side cowl vent attaches to the cowl and heater box? hanks
This car was originally an A/C model so no, I don't have that.
My other Charger was also. I converted it to a simpler heater/defroster but didn't use OEM stuff at the cowl, I used a rubber seal from Detroit Muscle Technologies.

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The seal just stays in place by pressure, there is no physical connection .
 
I'll have to go back a bit and look but from memory:
I do remember that the lower panel in Factory A/C cars here:


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....came with a new screen/grid/grille for the center. That came with some type on non stock style collar that the new ducts attached to.


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Thanks that was helpful. I finally got it cleared up talking to Steve on CA's tech support line, the diagram you included above shows the center vent connects to the back of the dash facia plate and the two center hoses attach to two oval openings on the back which is not shown anywhere in their manuals. Thanks again, question answered!
 
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