Where there manual A/C along with ATC

Zymurgy

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Do to my recent education on ATC, I feel like it would be a deal breaker when I get my next car, especially since A/C it is one of the main options I want on another car.

Were there manual A/C units along with ATC every year for our c-bodies? In case it matters most interested in 65-71. Did ATC start in 1967?
 
Do to my recent education on ATC, I feel like it would be a deal breaker when I get my next car, especially since A/C it is one of the main options I want on another car.

Were there manual A/C units along with ATC every year for our c-bodies? In case it matters most interested in 65-71. Did ATC start in 1967?


ATC was introduced during the latter part of the 1967 Model run which is why it does not appear in much of the literature for 1967. It was an extra cost option in addition to what would have been paid for standard A/C. It was initially only available on selected models, usually the higher end ones. As far as I am aware, standard A/C was generally always available on any model that offered air conditioning. No A/C of any type was available for any model with certain high performance options. Other than that, the two options existed side by side.

Dave
 
ATC first appeared in '67 only on Imperials, and I think it was a mid-year introduction. I don't think it's mentioned in the sales brochure, but you can easily double-check me on that, since you just got one. It was pushed heavy in '68, so you'll find it on most Imperials, many Chryslers, and even some high-line Dodges and Plymouths. It didn't take long for the system to start to get a bad reputation for reliability issues, and ATC installations dropped off a bit each year, but was still somewhat common on Imperial and New Yorkers. Sales ramped up again in the Formals with ATC II. The good news is that you could always get standard A/C in all models and all years.
 
Thanks guys for the education. FYI the '67 Imperial I looked at today was built on April 5th and had ATC.
 
It's also not a huge deal to switch an ATC system over to the standard set-up. The HVAC box is the same. You just need the standard heater valve and cable, control head and vacuum line set, along with some changes to the wiring. One exception is the '68 Fury, which uses a different dash finish panel between standard and ATC. May be the same situation for '68 Dodge too.
 
It's also not a huge deal to switch an ATC system over to the standard set-up. The HVAC box is the same. You just need the standard heater valve and cable, control head and vacuum line set, along with some changes to the wiring. One exception is the '68 Fury, which uses a different dash finish panel between standard and ATC. May be the same situation for '68 Dodge too.
This is good info to know, nice to know I can keep all my options open. If you and buddy get the ATC running on the 67 Imperial that will be interesting too.
 
Yep, that's all.. :rolleyes:

:p

I'm getting a reading on this one. :D

245785_5_.jpg


Maybe I'm the only one that spent my youth in junk yards, grabbing up non-ATC control heads out of nasty, wet and moldy cars.
 
On the "normal" a/c cars, there were some differences, depending upon the model. The A-cars (Valiants/Darts) used a cycling-clutch system, as did the aftermarket systems. Plus being "non-integrated" under-dash units.

I don't recall about the B-cars, if their compressors cycled or not. But the C-cars and Imperials all had constant-running compressors. The pressure modulation was from the Evaporator Pressure Regulator (EPR) valve located inline at the compressor.

One day, we were at the local Chrysler dealership and they were "converting" a recently-new Valiant to the non-cycling compressor, as the Chryslers/Imperials were. I was amazed at how easy it was! Just unhook the cycling switch, jumper the two wires together, and install the EPR valve in the a/c line at the compressor.

A friend was parting a '70 New Yorker out and offered me any parts I might desire. It was an ATC car. I was interested in why there was a metal screen in the intake side of the compressor line AND why it had a male wire terminal on it???!!! Like some sort of ground?

In the Chrysler MasterTech archive on the Online Imperial Club and/or MyMopar.com websites, there are training manuals on the first and later ATC systems.

From where I was in the middle 1960s, I never saw any ATC units until about 1969 on Imperials. That they existed as early as '67 on Furys and similar Dodges is not surprising as GM offered their ComforTron atc systems on all of their full-size cars (Chevy on up). I never worried about non-Chrysler C-bodies having it back then.

I don't know that I'd shy away from an ATC car, but for me, the normal a/c works just fine.

CBODY67
 
A friend was parting a '70 New Yorker out and offered me any parts I might desire. It was an ATC car. I was interested in why there was a metal screen in the intake side of the compressor line AND why it had a male wire terminal on it???!!! Like some sort of ground?

CBODY67

You got me on that one! I forgot all about EPR vs ETR valves.

EPR, or Evaporator Pressure Regulator for standard A/C

ETR, or Evaporator Temperature Regulator for ATC

The only purpose of the two valves is to prevent the evaporator form getting too cold and icing up. The EPR accomplishes this by raising the low side pressure and the ETR valve cycles the compressor off if it gets too cold.


Here's the deal on them for the 21'st century:

Most of the EPR valves ever made are now shot and don't work anymore, with the exception of some that were in cars where the A/C was always serviced and kept alive. A few years ago I was helping a friend get the A/C up and running in his Challenger and his EPR valve was stuck. I ordered three NOS valves, one for him, and two to put in inventory, and they were all bad. The thermal wax inside them just doesn't last forever.

Most people will be converting to R134, and when doing so on an RV or RV-2 equipped mopar, step one is to yank out the EPR valve and chuck it in the trash. You then install a universal temp sensing switch on the evaporator that cycles the compressor when needed.

I haven't messed with any ETRs, but it's likely that most of them are worn out too, so the same steps would apply to R134 in an ATC system.

The clutch cycling modification will also work fine if one was to stick with R12.

Jeff
 
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Jeff you give me hope in my on going A/C car search. We will need a full write-up on your buddies Imperial. I am guessing it might be pretty far down on the to do list, however. First would be just to get it home. :)
 
Jeff you give me hope in my on going A/C car search. We will need a full write-up on your buddies Imperial. I am guessing it might be pretty far down on the to do list, however. First would be just to get it home. :)

I'm not sure where it will fall on the priority list. He rarely uses A/C in the car or in the house (much to the chagrin of the rest of his family), but he absolutely wanted an A/C equipped car this time. If he doesn't get around to it in a timely manner, I may be able to spend a weekend next year diagnosing the ATC on one of my cars. I've been talking pretty big on ATC lately, and eventually people are going to want to see some results. :mob:

I have a 1970 Newport with ATC that stopped working after the car sat for 15 years, and it would be a good candidate to check out.

It's certainly preferable to get a car without ATC, but I wouldn't walk away from a nice car just because it had that option. I see that the hunt for a '69 T&C is back on and many of them left the factory with ATC. In '69 the Town & Country had a bit of an identity crisis. You got upscale items from the New Yorker, like the grill and woodgrain dash trim, which were then combined with taxi-cab door panels from the base level Newport. You can find some real bare bones T&C's out there, equipped with crank windows, woodgrain delete, and a 383 under the hood. Those will have standard A/C if they have A/C at all. If your tastes are a bit richer, and you are leaning towards a well-optioned car (like I would), there's a real good chance you'll find that temp selector knob when you look at the dash.

There it is on my '69 T&C. It's not a fully loaded car, but has most of the popular options.

69 T&C ATC.JPG
 
Sales ramped up again in the Formals with ATC II. The good news is that you could always get standard A/C in all models and all years.

I believe the Formal Imperial's 1974's and 1975's were only available with ATC II. ATC II was standard both years of these Imperial's with no option for manual A/C.
 
There were some dealers that had the "good sense" to not put too many ATC cars on their lots. Especially if the option (for Chrysler) was not fully understood by the public and the dealership techs. No real need to unnecessarily generate displeased customers from their existing customer base. Of course, there will always be those that want "the best", which can also mean "highly optioned" cars of a particular make. Every option including the tissue dispenser. IF it was on the showroom floor, even more prestige attached to it. BTAIM

I suspect that most of the ATC and ATC II cars were ordered (when it was optional) by large metro area dealers, rather than small town stores . . . unless it was a "sold order" or was an end of the year Sales Bank car that the dealer got for the cheap. In the 1960s, when GM did their Comfortron systems, there was still a bit of mystery of the system doing what it was expected to do, despite any overrides on 'no heater" until "the water got hot", for example.

By the time ATC II came out, things probably were much more evolved and simplified? Any mistakes in the design were probably "learned from", just as GM altered their design of "the programmer" every so often.

In the summer in TX, better to have a reliable normal a/c system that worked rather than an a/c system that worked at the whims of sensors and switches that had their own protocols of what should be done, when. Not unlike having one of the Flow-Thru Ventilation T-birds whose rear ventilation door would not close in a west Texas sand storm!

CBODY67
 
The last truly reliable and simple system I can remember

View attachment 157331

An uncle, with a young family, recently out of college, and headed into a sales job in the oil field in W TX, came to a family get-together one weekend . . . in a new 1962 Rambler American 2-dr sedan. That was the first Rambler I'd seen up close. I took that "Weather Eye" seriously and looked all around on the car, even under the hood, to see where "the eye" was. Like it was going to locate "the eye of the storm" for the car's occupants? Never did find it. He later sent me a brochure for the car, which explained that was their name for "heater/defroster". In that same brochure, to demonstrate how carefully the car body were stamped and assembled, there was a model, long evening dress, and elbow-length WHITE gloves running her gloved hands over the bodies of the cars on the assembly line to check for surface imperfections and such. I laughed, even then.

Funny how hvac controls have gone from knobs, to levers, to buttons, and back again. After Dodge bragged that construction workers could work all of the items on their then-new Ram pickup's instrument panel with work gloves on, at the next mid-term refresh, GM went from smallish push buttons to larger knobs on their pickups' hvac controls! LOL

CBODY67
 
There is a way to resurrect the ATC system and it bypasses the big vacuum servo.
You see, Chrysler sold the ATC system to Mercedes in 1975 and it was used extensively on their cars. I'm well versed with it due to 12 years of slinging Mercedes parts.
The Mercedes crowd demanded a fix and a little cottage industry popped up around it. Unwired Tools is one company that makes the electronics that replaces the vacuum servo and amplifier. It looks to be a drop-in for the Chrysler cars.
I have ATC on my 72 Imperial and have purchased the kit from Unwired. When I get everything up and running again I'll install the kit and share the results.
 
Very cool information. Looking forward to hearing about your results. Take lots of pictures during the process. :)

I checked out Unwired Tools, I love the little cottage industry. Which set up did you buy?
 
There is a way to resurrect the ATC system and it bypasses the big vacuum servo.
You see, Chrysler sold the ATC system to Mercedes in 1975 and it was used extensively on their cars. I'm well versed with it due to 12 years of slinging Mercedes parts.
The Mercedes crowd demanded a fix and a little cottage industry popped up around it. Unwired Tools is one company that makes the electronics that replaces the vacuum servo and amplifier. It looks to be a drop-in for the Chrysler cars.
I have ATC on my 72 Imperial and have purchased the kit from Unwired. When I get everything up and running again I'll install the kit and share the results.

Those replacement controllers are only remanufactured for the ATC II systems sold new in 1971 - 1973 chrysler products. For ATC 1 systems or the ones used in the formals, you are on your own...............
 
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