A/C Question? After Market System

Randy Miller

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I just tore out the whole factory AC heater system from my 67 Dart GT. I was wandering if it was easier to just put the heater system back in and add the after market AC later OR do the whole thing? Could it be a expense I could put off for now? Thanks for the help.
Happy Thanksgiving!
 

str12-340

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The two main brands of modern AC systems are just like your stock system - heater and AC all in one unit. There used to be add on units that were separate from the heater on heater only cars, but they are real dinosaurs. When you say "I tore out the whole AC system", do you mean all the stuff under the hood, or under the dash too (which would remove your heater too)? If the stuff is still under the dash, you can continue to use the heater part of the system until you are ready to do something about it. I've been driving one 70 Dart since 1978 using the heater without any of the underhood AC stuff and it works fine.
 

my68barracuda

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I just tore out the whole factory AC heater system from my 67 Dart GT. I was wandering if it was easier to just put the heater system back in and add the after market AC later OR do the whole thing? Could it be a expense I could put off for now? Thanks for the help.
Happy Thanksgiving!
I added AC to my 68 Barracuda using a Classic Auto Air system. The instructions were good, the parts fit fine, the AC works great. With Classic Auto Air you re use the OE dash heater/ vent/ temp control unit, with some modifications. The advantage of a new unit is the modern AC components, compressor, condenser,, are more efficient than the 50 year old parts. most likely your OE compressor needs new seals and your OE hoses and dryer needs to be replaced anyway.
One thing to keep in mind is the Classic Auto Air unit is made for cars that did not have factory AC, I believe the firewalls in the AC and non AC cars are different. The dash heater/ vent/ temp control unit may also be different between AC and non AC cars. For the firewall difference I have seen postings on the internet where folks came up with a work around. Classic Auto Air could give you the best guidance on fitting their unit to an OE AC car.
 

Mike69cuda

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If you still have all the original ac stuff from the car, that would be way cheaper to put it back. You can buy kits to rebuild it. I don’t think you can just use the heater portion of the box under the dash alone with the ac part (the ac part under the dash) removed. As said above, the heater will still work with the under hood components removed, as long as you leave the vacuum hooked up.
 

j par

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I did an after-market 22,220 BTU under dash unit for $475 From coldmaster.. that included the under-dash evaporator the compressor the condenser the dryer all the hoses clamps under-dash bracket and wiring harness. The only thing I had to provide was the bracket for the compressor and two $5 cans of 134 freon... I went to Harbor Freight and bought a vacuum pump and the gauges,but those can be both rented for free at the local AutoZone...
 

Randy Miller

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The two main brands of modern AC systems are just like your stock system - heater and AC all in one unit. There used to be add on units that were separate from the heater on heater only cars, but they are real dinosaurs. When you say "I tore out the whole AC system", do you mean all the stuff under the hood, or under the dash too (which would remove your heater too)? If the stuff is still under the dash, you can continue to use the heater part of the system until you are ready to do something about it. I've been driving one 70 Dart since 1978 using the heater without any of the underhood AC stuff and it works fine.
I did tear out the heat core housing to get the rat stuff out. I did not remove the AC housing. I will leave that in there and replace the heater housing and core when I clean it up. Thanks so much for the advise. I just wanted to spend money on the car right now not the AC
 

Randy Miller

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If you still have all the original ac stuff from the car, that would be way cheaper to put it back. You can buy kits to rebuild it. I don’t think you can just use the heater portion of the box under the dash alone with the ac part (the ac part under the dash) removed. As said above, the heater will still work with the under hood components removed, as long as you leave the vacuum hooked up.
All that is left from the original AC is under the dash housing and condenser. Not much to work with if I went back to stock. I will move on to getting the car put back together then years down the line I will install AC. Thanks
 

str12-340

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just to be sure you know, you can't just put a heater box from a non-AC car into an AC car - the whole firewall is different.
 

BillGrissom

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I would keep the OE climate box. You should be able to use the AC condenser. The other parts in the engine bay can be modernized, though you might want to keep the expansion valve. My A's were non-AC, so I added an under-dash knee-knocker AC box, but it greatly adds clutter and seems silly to have 2 different blower motors. I could have used a new climate box, but it wouldn't work with my dash cables. Most have a separate remote.
 

Randy Miller

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I would keep the OE climate box. You should be able to use the AC condenser. The other parts in the engine bay can be modernized, though you might want to keep the expansion valve. My A's were non-AC, so I added an under-dash knee-knocker AC box, but it greatly adds clutter and seems silly to have 2 different blower motors. I could have used a new climate box, but it wouldn't work with my dash cables. Most have a separate remote.
I will leave in the AC box under the dash then and do that project later. Thanks for the help.
 

GGs66GT

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Ok tech terms
The thing inside is the evaporator
The thing in front of the radiator is the condenser.

So you have the inside a/c stuff and the heater , Great .
When you get around the making the a/c work you will need to flush the evaporator of oil as the R 12 oil in it is not compatible with R 134a you will need to add the 134 type of oil to the system .

Under the hood change the condenser , dryer , hoses , and compressor to R 134a compatible components .
You can clean and reuse the expansion valve .
As for the compressor you can get a reman V2 for R134a or spend for new brackets and go with a Sanden which is more efficient and uses less H.P.

The R134 condenser is the manifold type . It has a manifold on each end . The freon flows across the condenser instead of the R12 type where it zig zags through the tubes .

The R134 hoses have a bearer lining in them because the R134 molecules are smaller than R12 .

Use the green o rings not the black

The dryer has a different desiccant the the R12 units

The use R134 oil only .

Adding a trinary switch will protect the compressor if there is a leak .

There are a few threads on the members restoration forum dealing with rebuilding the heater and a/c inside units .
 

Randy Miller

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Ok tech terms
The thing inside is the evaporator
The thing in front of the radiator is the condenser.

So you have the inside a/c stuff and the heater , Great .
When you get around the making the a/c work you will need to flush the evaporator of oil as the R 12 oil in it is not compatible with R 134a you will need to add the 134 type of oil to the system .

Under the hood change the condenser , dryer , hoses , and compressor to R 134a compatible components .
You can clean and reuse the expansion valve .
As for the compressor you can get a reman V2 for R134a or spend for new brackets and go with a Sanden which is more efficient and uses less H.P.

The R134 condenser is the manifold type . It has a manifold on each end . The freon flows across the condenser instead of the R12 type where it zig zags through the tubes .

The R134 hoses have a bearer lining in them because the R134 molecules are smaller than R12 .

Use the green o rings not the black

The dryer has a different desiccant the the R12 units

The use R134 oil only .

Adding a trinary switch will protect the compressor if there is a leak .

There are a few threads on the members restoration forum dealing with rebuilding the heater and a/c inside units .

Great information. When I get to rewiring you might be the guy to ask questions. Things are going well to this point. I will keep you posted. Thanks
 

BillGrissom

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Great information. When I get to rewiring you might be the guy to ask questions. Things are going well to this point. I will keep you posted. Thanks
You don't have to use R-134A. Indeed, it is being outlawed and no longer ships in new cars for several years. I use HC refrigerant (Duracool, Envirosafe is another). It works better than R-134A, indeed even slightly better than Freon (R-12). It is compatible with mineral oil, but I would still flush out the evaporator and install new "barrier" AC hoses (Viton lining). I use PAO 68 oil, which is compatible with all refrigerants and more efficient. Ignore the crazy claims that HC refrigerant can "explode". Those ranters know nothing about combustion. Millions of cars use it with no fire ever reported. All refrigerants burn, if not themselves, the oil which sprays out with them, and many form very toxic products when they burn. If you don't buy a MasterCool ferrule crimper, you can use Oeticker stepless ear clamps (ebay) or even the similar PEX crimps at Home Depot.
 

Randy Miller

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You don't have to use R-134A. Indeed, it is being outlawed and no longer ships in new cars for several years. I use HC refrigerant (Duracool, Envirosafe is another). It works better than R-134A, indeed even slightly better than Freon (R-12). It is compatible with mineral oil, but I would still flush out the evaporator and install new "barrier" AC hoses (Viton lining). I use PAO 68 oil, which is compatible with all refrigerants and more efficient. Ignore the crazy claims that HC refrigerant can "explode". Those ranters know nothing about combustion. Millions of cars use it with no fire ever reported. All refrigerants burn, if not themselves, the oil which sprays out with them, and many form very toxic products when they burn. If you don't buy a MasterCool ferrule crimper, you can use Oeticker stepless ear clamps (ebay) or even the similar PEX crimps at Home Depot.
Awesome. Thanks
 

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