A/C questions and ramblings

[shadango]

Have no immediate plans to get the A/C in our 80 Volare going.....I figure the kiddo can muddle through with no A/C just like his Dad has to inb the Barracuda...LOL....let him develop an appreciation for it.

That said, I am just sitting here pondering things and the A/C came into my mind.

We know the compressor works , or seems to....when we got it and tried charging it, it runs but cycles on and off too fast and eventually stops working altogether as the charge leaks out.

No apparent leaks anywhere, of course the engine bay has been cleaned at this point.

I figure: two hose assemblies....condensor, evaporator , accumulator/drier

All those parts are easy to replace . And parts available on Rockauto..though I didnt see hose assemblies.....EXCEPT for the evaporator---buried deep in the bowels of the dash.

The heater box in my 72 Cuda is a breeze to get in and out but the box in the 80 Volare looks like a real PITA. Anyone have any feedback on that in particular?

The hose assemblies look fine but we all know how that goes.

The biggest issue I see if that evacuating the system and recharging has to be done and if there is still a leak after replacing one item it has to be redone again.....rinse and repat til you get it right. That will get $$$$$$.

Any other feedback as far as a tact going forward should the A/C eventually rise to the priority level currently filled by more important issues?

 

[Aspen500]

You're best bet, and will save cost in the long run is to have the system charged, or even partially charged, along with florescent A/C dye (shows up with black light and special goggles). That way you will know for sure where the leak is, or leaks are.

If you convert to R134a it'll be WAY less expensive. R12 goes for $70/lb around here IF you can find a shop with a supply. R134a is around $18/lb. Easy process to convert over. All your existing parts will be fine. Really only need to get as much of the mineral oil out as possible and use the PAG oil instead. The non-barrier R12 hoses become barrier hoses after years of the mineral oil in them and the new refrigerant won't "leak" through the hose. Screw the R134a charge fittings onto the R12 fittings and it's a good idea to swap the binary low pressure cycling switch with a trinary that disengages the clutch with both low and high pressure. Screws in the same spot and takes the same connector.

Assuming an '80 is similar to '79, the HVAC plenum isn't all that hard to remove. Basically you take the bottom half of the instrument panel off, remove the console (if equipped) and of course unhook the hoses and lines under the hood along with a few nuts.

 

[BudW]

The ’80 uses the ’80-89 FMJ style Evaporator case design – which is way different from the ’76-79 design.

I have removed the evaporator cases on a ton of these cars – and in my opinion, it is not hard to do.
Taking the dash apart and keeping the screws separate (as well as not lost) is the big job.

I would agree with Aspen500 and get the A/C system leak checked first. These evaporator cores are not known to be big leakers as some other carlines are. No need to remove and replace something that is not needed to.

Also, I recommend converting to R-134a if you can, for R-12 is not easy to find. The A/C systems on our cars work fine with R-134a – providing you get all traces of old refrigerant oil out of the system, first.

My recommendation is to take car to shop that does A/C work. Have them perform a leak check on car. If a leak is found, then have then evacuate your existing refrigerant and document how much was removed. You go attack the source of the leak, then take car back to them to have the evacuation and recharge performed.

The evacuation and recharge is the part most people don’t have the equipment to do.
The rest of the A/C work I have confidence you can do.

If a problem if found, let us know and we can get you instructions to “get it done”.

Note: most A/C jobs both of you can do. Matter of fact, dash work is great for two people. One on each side of dash. One person doing the screwing then onto the next person. The non-busy person with Ziploc baggies and a marker marking down where screws came from, and so forth.
Great for father/son time.

I can remove an evap. case assembly in about 30 minutes, by myself, and about as much time to re-install (not counting evac/recharge). First timer - I would say about triple that time.
BudW

 

[BudW]

Assuming an '80 is similar to '79, the HVAC plenum isn't all that hard to remove.

The systems are completely different but procedures to remove/replace are the same and time to do it is about the same.


Aspen500, I wonder if your ’79, has an ’80 evap. Case in it already – sense it has those things different about your car.
The ’76-79 has a different case for the blower motor. The heater core and evaporator core are in a separate case. It also has that firewall crossover between the two units.

The ’80 up case contains the blower motor, heater core and evaporator core (all in one).

 

[Aspen500]

Forgot all about the diff between the '80 and earlier cars.
Mine has the external duct as part of the firewall and 2 pc plenum with the separate blower housing. It came from a '78 parts car, as did the firewall from the cowl down and inner fender panels. My car wasn't originally an A/C car and during it's semi pro-street days, had no inner fenders and the firewall was tunneled, fenderwell headers, etc, etc, etc. (What was I thinking in the early '90's????)

 

[rcmaniac791]

Since we are all talking A/C here, might as well ask:

I did some A/C work not too long ago. replaced the hose going from the compressor to the condenser. Charged the system with R12a (worked fine) and it worked good for awhile. I even put in new compressor oil. The clutch started cutting on and off again like it was losing its charge, and that's when I noticed that the bottom left of my condenser was puking everywhere.

I guess the question I have is that is it ok to put a condenser in and then wait no more than 24 hours to put a vacuum on the system and recharge? I just want to make sure it won't mess anything else up. I'm no expert in A/C work...lol

Edit: I know not to turn the system on. It's pretty much all leaked out now.

 

[BudW]

Refrigerant and refrigerant oil should be the only thing in the A/C lines. The only reason oil is there is to keep the A/C compressor lubricated. Anything else doesn't contribute to heat transfer. Water moisture more so – for even a few drops of water moisture will freeze, stopping refrigerant flow (one of two different versions of “freeze up” (one is external and other internal)).

Water under a vacuum will boil at room temperature, at a certain level of vacuum – depending on, well, temperature and altitude. Most cases roughly 29” vacuum.

You vacuum down an A/C system for about an hour to get any/all traces of water moisture out of the system. As water boils, it turns into a vapor - which gets sucked out.

If you lived someplace that is very dry and high, then you can evacuate system for a lot less than an hour.

Personally, I like to get hoses hooked up, start the evacuation process, then start bolting on what ever else needs reattached (less down time).

Also, if you shut the hoses at end of the hour, then watch gauges to see if any drop (after compressor is turned off). If gauges drop, then you still have a leak that needs fixing.

If you perform an A/C repair and don't get around to evacuating the system, then not to much to worry about except for possibility of rust. Just make sure all water and non-refrigerant substances (ie: air) is out before refrigerant goes in. I would recommend vacuuming the system first – but you gotta do what you can, sometimes.
BudW

 

[shadango]

This is all great info guys, thanks.

Wish I knew someone with a vacuum machine......shop time is expensive.

I hate "having" to go to a shop for what is basically a luxury....

 

[JohnRogers]

It looks like a few major components of my factory A/C needs replacing. F-body replacement parts are getting scarce. Any reason why this shouldn't work?
1974 Dodge Dart Sport - Sport 340 | Dodge AC (at https://www.classicautoair.com/shop/1974-dodge-dart-sport-sport-340-air-conditioning-system/ )

 

[BudW]

It can work, with modifications (like hammering a round peg into a rectangular hole).

- The A/C control head is a lot different (looks close, but no cigar).
- The firewall is not quite the same.-
- The engine components will work great – if you currently have a small block.
- The condenser will need some modification for brackets to fit.

Personally, I would use a factory ’76-89 FMJ A/C condenser (even a used one). It will be twice as thick and a whole lot more efficient than any aftermarket condenser will be. They even work great for R-134a refrigerant conversions. Also it fits without any problems.

No matter what you do, you will have to modify the firewall to get anything to fit, correctly.

I would see if they would offer the kit less condenser and get the rectangular control head that fits our cars. If so, then let the modifications begin.

I think a person can find factory parts for a whole lot less money, even with a new evaporator core and using the same A/C compressor as in the above-mentioned kit.
BudW

 

[JohnRogers]

It can work, with modifications (like hammering a round peg into a rectangular hole).

- The A/C control head is a lot different (looks close, but no cigar).
- The firewall is not quite the same.-
- The engine components will work great – if you currently have a small block.
- The condenser will need some modification for brackets to fit.

Personally, I would use a factory ’76-89 FMJ A/C condenser (even a used one). It will be twice as thick and a whole lot more efficient than any aftermarket condenser will be. They even work great for R-134a refrigerant conversions. Also it fits without any problems.

No matter what you do, you will have to modify the firewall to get anything to fit, correctly.

I would see if they would offer the kit less condenser and get the rectangular control head that fits our cars. If so, then let the modifications begin.

I think a person can find factory parts for a whole lot less money, even with a new evaporator core and using the same A/C compressor as in the above-mentioned kit.
BudW

Bud, thanks for the well thought out reply. I placed my order at Rock Auto for most of what I needed. I got a compressor elsewhere since my guy doesn't want to build one. Reman AC Compressor & A/C Clutch For Dodge Dart Van Pickup Chrysler & Plymouth | eBay

 

[Dr Lebaron]

THIS
Works for me.

 

[Dr Lebaron]

Bud, thanks for the well thought out reply. I placed my order at Rock Auto for most of what I needed. I got a compressor elsewhere since my guy doesn't want to build one. Reman AC Compressor & A/C Clutch For Dodge Dart Van Pickup Chrysler & Plymouth | eBay

I have 1989 M used compressors and other stuff.

 

[BudW]

I got a compressor elsewhere

The Chrysler RV2 (or sometimes referred as RV or V2) compressor is one of two that I know of that has an oil pump built-in. The other one is the GM A-6.
All the rest of them either uses a connecting rod extension that splashes oil (think small engines, like lawn mowers) or uses oil in the refrigerant system (only) to lubricate parts. It works – but, um, not real well.
Ask yourself how many times have you heard of an automotive A/C compressor that needed replacement?

The RV2 compressor rarely goes bad. The only things I know of that gave problems was the front crank seal. The crank seal tends to leak mainly when A/C system hasn’t been used for long periods of time. It uses the compressor oil for sealing purposes and works great when A/C is used at least occasionally.

The disadvantage to the RV2 compressor is its weight and size.
It is like bolting a hefty battleship anchor onto the side of a small rowboat.

The RV2 compressor also works well with R-134a (if all old R12 oil has been removed, or not yet installed).

When I get the big blocks installed into my cars, I plan on using the RV2 compressor on my ’77 (which is what it would have had if car had A/C) and C-171 on my ’86 (which will require some bracket fabrication) - but that is just me.

The Sanyo A/C compressor that may big blocks use as a conversion compressor is a good unit (for not using an oil pump) - but it doesn't give the "look" that I want.
BudW

 

[Justwondering]

shadango -
last year (wasn't it BudW?? or was it 2 years ago now), I managed to convert my fifth avenue over to 134a. I did replace the compressor. Did the PAG oil with the dye.

It was my 2nd big activity with the car and my first mechanical event.
Everything went well right up until I tried to remove the compressor... took 2 days to figure out I had missed on the big bolts holding it in - the one at the rear.

I did take it to the mechanic to have him backstop me on the work and other than 1 washer that was not sitting flush in one of the lines, things went well.

I tell you this, cause I was a complete novice and was able to square things away (albeit somewhat slowly). And I did rely on someone else to vacuum the lines and install the refrigerant/check for leaks for the same reason you spoke of (no reason I could justify the very occasional expense of a vacuum pump).

Its all doable and like BudW says -- using baggies and a sharpie to keep track of things as you take them apart makes it much easier when things go back together.

Sounds like you are more polished about cars than I, but if I could get mine back up and working I'm positive you can as well!

Good Luck,
JW

 

[shadango]

I have removed the evaporator cases on a ton of these cars – and in my opinion, it is not hard to do.
Taking the dash apart and keeping the screws separate (as well as not lost) is the big job.

I would agree with Aspen500 and get the A/C system leak checked first. These evaporator cores are not known to be big leakers as some other carlines are. No need to remove and replace something that is not needed to.

Also, I recommend converting to R-134a if you can, for R-12 is not easy to find. The A/C systems on our cars work fine with R-134a – providing you get all traces of old refrigerant oil out of the system, first.

My recommendation is to take car to shop that does A/C work. Have them perform a leak check on car. If a leak is found, then have then evacuate your existing refrigerant and document how much was removed. You go attack the source of the leak, then take car back to them to have the evacuation and recharge performed.

The evacuation and recharge is the part most people don’t have the equipment to do.
The rest of the A/C work I have confidence you can do.

If a problem if found, let us know and we can get you instructions to “get it done”.

Note: most A/C jobs both of you can do. Matter of fact, dash work is great for two people. One on each side of dash. One person doing the screwing then onto the next person. The non-busy person with Ziploc baggies and a marker marking down where screws came from, and so forth.
Great for father/son time.

I can remove an evap. case assembly in about 30 minutes, by myself, and about as much time to re-install (not counting evac/recharge). First timer - I would say about triple that time.
BudW

Hey Bud.....so it took a year + for us to get back on this topic but we are there...LOL

Took the car to an AC shop that has been around for ever.

Like anything else its a bit of a can of worms.

He suggested the conversion to R132A as well, said finding the leaks etc will be much cheaper.

So we did that.....He said he found two leaks....one was the the hoses at the top of the compressor (I knew that would be one) and then another -- an oring at the condensor as I understand it.

Said the compressor seems ok....was pressuring the system....but was showing high readings on high side, low on the low.... meaning there is a clog somewhere....so he had us get a block valve as it was clogged and then and a filter drier unit.

Said the lines are pretty crusty inside....compared them to someone with clogged arteries. he is letting them soak with cleaner in them as well as the condensor and is hoping to clean them all out and use.

Wondering if it doesnt make more sense to just buy new ones (only available thru NAPA from what I can see??)....worried that cleaning the pipes/hoses may just net new leaks...LOL...but trusting the guy.

He seems optimistic, but I am hoping I am not just throwing good money after bad. He said we are at about $500 right now plus the parts I provided.

 

[shadango]

Looking further into it, none of the parts houses including rockauto seem to carry replacment hoses assemblies.....napa lists complete assemblies, bit only for the v8 models of our car......I guess they are different than the slant 6 version?

NAPA said they can make NEW hose assemblies, using my old metal parts where needed and they also have some of the more generic metal tubes etc.

The shop is soaking the hoses/tubes as it is.....do I have any other options?

 

[BudW]

If I was going to spend money on A/C hoses – I would replace (hands down)

eBay is where I have found a lot of new hoses at – but new hoses haven’t been in production for some time now.

/6 and small block (as far as that goes, big block) A/C hoses are almost the same – except for hose length (which differs on all three engine types).
There are also differences between the RV2 and the C171 A/C compressors, as well.

NAPA did sell new metal ends for hoses (or still does). If they do, then you can easily get new hoses made up for your car. The plus side is the newer hoses are so much better material than what was used forty years ago.
I would rather have a new hose made with new ends, if possible (or that is my opinion, anyway).
BudW

 

[Aspen500]

May have been mentioned earlier but, the R134 hose is barrier hose and needs a different type of metal end and, they must be bubble crimped. Just an FYI.

 

[shadango]

If I was going to spend money on A/C hoses – I would replace (hands down)

eBay is where I have found a lot of new hoses at – but new hoses haven’t been in production for some time now.

/6 and small block (as far as that goes, big block) A/C hoses are almost the same – except for hose length (which differs on all three engine types).
There are also differences between the RV2 and the C171 A/C compressors, as well.

NAPA did sell new metal ends for hoses (or still does). If they do, then you can easily get new hoses made up for your car. The plus side is the newer hoses are so much better material than what was used forty years ago.
I would rather have a new hose made with new ends, if possible (or that is my opinion, anyway).
BudW

I looked on ebay and found nothing compatible with the /6.

Gonna see if the old hoses hold. Worse comes to worse we have to top off at some point. I know a guy with a 72 Mustang.....replaced his r12 with r134a and nothing else and has had no issues.....an older fellow, has had the car for years.

I know I can always get the hoses made....I am sure that wont be cheap...LOL

I am just crossing my fingers the bleed stops soon and we have A/C. LOL I really opened up a can of worms....but I promised the kiddo it for his graduation gift so, have to follow thru!