Comfort control-restore or convert?

[CadillacMac]

Hello all, looking for opinions here.  I've taken the compressor off to have it rebuilt.  But before I do that, I want to know what the club members think.  As I start this process, should I get one of those modern upgrade conversions I've heard about?  Do they look original like some other conversions?  Any suggestions?

Or do I stay old-fashioned and keep the system as-is, restoring piece by piece? 

I don't want to change the controls. 

I would LIKE to stay all-original under the hood, but having painted this gray old lady fire engine red in high school, I suppose the ship sailed on show-worthy originality. 

[TJ Hopland]

What year and how long since it last worked?

Is cost a big issue?    Are you in the USA?   

How much of the work will you be doing yourself?   If not doing it yourself you will have to ask who is doing the work some shops may not work on original stuff and others may not like piecing together aftermarket parts.  Some shops don't mess with R-12 anymore. 

[Scot Minesinger]

Looks like you are dealing with 1965 or 1966 Cadillac, but my advice would be the same for 1964 thru 1979, keep it factory because there is not really much a good alternative.  I have restored more than a dozen of these 1965-76 climate controls so that they operate as new and are durably repaired.  The only change I make is converting to r134, that way they can be serviced far more easily and affordably.  The r134 seems to be more than adequate in the 1971 -1976, but not quite up to the to the task in 1965-1970.  The r134 cools well below 85'F outside, and takes the sting out of 85'F and above heat in the 1965-70 Cadillacs, half of which seem to be convertibles, so top up climate control on in rain mainly - no problem.  If you live in a hotter climate, top up/closed Cadillac then go with r12.

The factory compressor and all the parts are available to restore your Cadillac climate control.  Cadillac Tim published a book on each year of Cadillac climate controls (google Cadillac Tim in Iva SC), he sells all the rebuilt part too.

The main reason to go factory, is that the dash controls coupled with the duct controls behind dash, are really so difficult to replace with modern controls.  Plus if you keep it factory operational, it will keep more options open for you when you go to sell.

[30326]

I agree with Scot. Buy a copy of Cadillac Tims 1964-76 Cadillac Climate Control Troubleshooting Manuals. Its well worth the money spent.
http://cadillactim.com/.

Also understand that a full conversion from R12 to R134 will set you back at least 700USD. A really good blog on conversion was written by Michael Forte and posted on the 63/64 Chapter.
http://6364cadillac.ning.com/profiles/blogs/converting-to-r134a-on-my-63

Cheers

["Cadillac Kid" Greg Surfas 15364]

First of all, what year are you working on?  If it is 64 and later there are quite a few significant differences in the systems that must be dealt with IF you are going ot switch to R-134a.  The best case scenario would be a 20% decrease in cooling capacity if you just change refrigerant, leaving all the components as is.  Ifr you go to a POA eliminator ((66 and later) you will loose the continuous de humidification feature of the Automatic Temperature Control (ATC)  I'm going to guess that living where you do you probably want to keep Humidity control, and you probably don't want to loose that much capacity.  You can keep your system operating on R-12 since it is available and will be for some time to come.  A GOOD AC shop will be able to charge your system with R-12, or if you are doing it yourself it is available.
In regards to keeping you system original, we need to know what year are you working on.
Greg Surfas

[cadillacmike68]

I don't know where everyone keeps saying you lose 20% cooling capacity with R134. That's Not been my experience, and I live in FL where its still 85 & up every day. With the correct POA you can get 100% of original capacity and still not lose the constant De-humidification or the always running A6 compressor. The 65-70s have ginormous condensers that are more than adequate to cool very effectively.

[Scot Minesinger]

Mike,

You are the only one who I know writes this.  The properties of the R134 vs r12 make this so.  If you were able to install r12 back in the car it would likely be 20% better.

The 1971 thru 1976 condensers are even larger, and are adequate to cool these Cadillacs down better than the 1965 thru 1970 Cadillacs believe me.  I have restored over a dozen, maybe 20 of these systems and every time the 76 era Caddies cool so well while the 1970 and below do not cool as much.  This includes the POA recalibrated to r134 at the same place you had it done, Old Air Products or the other in FL.  It is just an inescapable law of physics.

In any event, it is great that you are so satisfied with your Cadillac!  I am too, so we are both good to go.  Drove mine yesterday, the day before and the day before that.  Probably again today too.  However, heat is needed.

["Cadillac Kid" Greg Surfas 15364]

Still waiting on the year ATC we are talking about.
Greg Surfas

[cadillacmike68]

I don't Scot, Air temp out of the center vent of 42-44F when its 90F or higher outside is about a good as any system is ever going to do.  In addition to Classic Auto air (the FL shop) the person who tuned my system really knows his AC and ATC, and he is able to get the max performance out of a system. My POA is a new one as well. That probably has a lot to do with it. Iy also makes it more difficult to get the #7 plug out.

He went through my 1996 Fleetwood which was icing and not only does that car not ice up any more it will just about freeze you out when set down to 65. They flushed the system for a loooong time, got any debris out, changed the filter up front and I put a new compressor on (the old one worked, but that debris had to come from somewhere). It's been great since.

The OP hasn't written back, but "Comfort Control" was used starting in 1964. By 1967 it was "Climate Control". I'm not sure when they changed the name to "Climate Control".  My brochures are all in the trunk, so I'll look later. Perhaps the OP will come back and let us know the year.

[cadillacmike68]

In 1965 it was still called Comfort control, but in 1966 it became Climate Control. I'm pretty sure the two years have identical systems. So the car in question is either a 1964 or 65.

["Cadillac Kid" Greg Surfas 15364]

"Automatic Temperature Control" (ATC) where you set the dil on the numerical temperature you are trying to achieve came out in 1964.  The refrigeration and electric/vacuum control systems were quite different in the first few years.  Each subsequent year intending to correct the deficie3ncies discovered in the design of the previous one.
Greg Surfas

[cadillacmike68]

^^^ Agreed Greg, but some parts, like the "steamboat switch", aka Master Switch were the same from 1964 up through 68, and I think even 1969 on Eldorados - make that 1970. The time delay relay vacuum loop is also the same from 67-70 (and perhaps going back to 64). The A6 compressor was essentially the same al these years, just the back mounting arrangement changed.

The POA / Expansion Valve / Suction Throttling assembly might have undergone changes from 1964-70, but condenser would have only been a size / shape issue because there are no moving parts. Same for the evap core and heater core.

I'm trying to find a decently priced Cadillac paper master interchange book(s) so I can be better able to tell what works with what; ideally one that covers from 1965 thru 1975-76.

The control heads and power servos definitely changed at least every other year, with 64-66 being complete unknowns to me and that's the year range we are talking about here so I'll step back and wait for the OP to chime back in.

["Cadillac Kid" Greg Surfas 15364]

Mike,
Not to be a (you fill in the blank), but there were significant changes in the evaporator and condenser internal and external circuiting/configurations/piping as well as the obvious differences.  The original poster asked about modifying or retaining originality, so the exact year configuration is important.
By the way the same master switch was used on much later "dual circuit" systems.
Greg Surfas

[cadillacmike68]

Mike,
Not to be a (you fill in the blank), but there were significant changes in the evaporator and condenser internal and external circuiting/configurations/piping as well as the obvious differences.  The original poster asked about modifying or retaining originality, so the exact year configuration is important.
By the way the same master switch was used on much later "dual circuit" systems.
Greg Surfas

Greg, understood, but as I noted the evaporator core and Condenser (and heater core, which is probably leaking by this point) still have NO MOVING PARTS. You get the right size for your year car and hook up the lines / hoses to them, and that's it, regardless of what refrigerant you use. I was Not trying to propose using a "different" one of any of these three.

The Suction Throttling / POA / Expansion Valve assembly, that is very year specific (or at least every other year), as I also noted. But a newer one (optimized for R134a), is close in appearance to the original. I didn't mention the receiver / dryer up front next to the condenser. That might have changed from 64-70. I'm not sure, but the correct ones are available, and I don't think that piece cares what refrigerant is going through it either.

There's nothing worse than a nice original looking car with an ugly welded aluminum radiator and condenser staring you in the face when you lift the hood, but the POA assembly is way in the back and is not nearly as noticeable. Even still original looking ones are still out there.  The only other things that will catch your eye are the R234a fittings. There is no mistaking these (If one know the difference), but they are small and not as noticeable as the POA assembly.

The OP is likely going to have a bigger problem with the Power Servo up on the firewall, and the control unit in the dash than with any of the items under the hood. That and bad / missing vacuum lines, connectors. There are many small switches in those two things and they both have the rotary vacuum valve assembly which is prone to failure (but it can be repaired).

["Cadillac Kid" Greg Surfas 15364]

Let's wait until the OP gets back to us.
Greg Surfas

By the way, circuiting, internal tubing finish and fin vs tubing surface areas determine the capacity of Any heat transfer device at least as much as does the physical size.

[Scot Minesinger]

His picture shows half of rear bumper passenger side of what looks to be a red 1965 Cadillac, might be a 1966 (Greg you would know differences in this shot of 1966 and 1965 better than me). 

In my experience the 1965-1968 climate/comfort control systems are the easiest to work on, followed closely by the 1971-76 Cadillacs (bad quality electrical wiring harnesses-finding the issue is main problem).  The 1969-70 are the most difficult due to removing dash unit and under hood heater/ac fiberglass housings (have four very difficult to get to screws on inside for under hood assemblies to be removed).  The worst problems are finding where audio installers messed up the under dash wiring/vacuum hoses.

In any event, to keep an original look under the hood and in dash, generally a stock restoration will probably be best.  I could see going to a higher capacity condenser (if it is 1965-1970) that looks stock to keep the inside cabin cooler in a/c if r134 is used.  Probably best to find out what year for sure to continue advising.

[cadillacmike68]

The pic, thanks Scot for pointing it out, looks like a 1965. The chrome bumper goes all the way down. In 1966 the bottom has body color sheet metal.

This would also fit in with "Comfort Control" because this was the last year for that phrase, the 1966 and on models calling it "Climate Control". I Still think 65 and 66 are very similar WRT the ARC system. Cadillac Tim would know.

[cadillactim]

The dash controls are the same 65-66. The only change is the faceplate. 65 had Comfort Control, 66 had Automatic Climate Control.

Early 65 models still used the old vacuum suction throttling valve like the 64 models. Late 65 models changed over to the newer valve.

Although many interchange them, the 65 and 66 power servos are different, and 66 used a blower relay, 65 did not.

Tim

[CadillacMac]

Goodness guys, I'm so sorry I posted and ghosted!  I suddenly got sidetracked by having to change my rear bearings, then cracked brake shoes, then busted wheel cylinders...one thing always follows another.

Plus I'm so used to my posts only getting a reply or two that I didn't check back very quickly!  Looks like this is a lively topic!

So no I'm back to A/C.

My apologies, I thought it shows the year car I have under my name.  It's a 1965 Fleetwood.  Everything is original but I think back in the 90s someone convinced my granddad to change the refrigerant, because the valve looks converted.

I want to rebuild the compressor with someone like Classic Auto Air, hoping it will be a little bit better than getting a Chinese "new" one off Amazon or something.  Although I'm sure Chinese parts are used in the rebuild.

After I send off and get the compressor and dryer bottle done, (looks like the dryer coming apart inside is what wrecked my system back in the day and locked the compressor) I'll probably rebuild some hoses and get a replaced power servo since the diaphragm doesn't seem to be holding vacuum. 

I will most certainly get Tim's book, and have already talked to him about a servo with it.

My question is, is that enough (rebuilt compressor, dryer, hoses, power servo) to get started in the testing and such, or should I plan on a new condenser, evaporator, switch assembly, transducer, etc? 

[CadillacMac]

What year and how long since it last worked?

Is cost a big issue?    Are you in the USA?   

How much of the work will you be doing yourself?   If not doing it yourself you will have to ask who is doing the work some shops may not work on original stuff and others may not like piecing together aftermarket parts.  Some shops don't mess with R-12 anymore.

I'm here in Georgia, I'm not loaded, but I'm ready to spend a what it takes.  Thankfully I've got a restorer with a lift as a friend, and he'll charge me a pretty reduced rate to go over the system with him and make fixes.  I would imagine it hasn't worked in 20 years or so.