1968 new yorker auto a/c

todd sherrod

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a new problem with my new purchase . any of you folks have experience on the auto a/c - heater system on the 68 c body ? I talked to a retired wrench from a Chrysler store and he told me GOOD LUCK ! what going on is - when and only when the high defrost mode is engaged the blower will cycle in short bursts , no other mode does anything , I can jump the blower and fan works good , maybe control head ? I have a manual but they are listing old oem tools for come of the diagnosis to continue - any help appreciated !!!
 
There are no parts available for these misersable and unreliable systems anymore, so trouble shooting will not do any good. The main culprit is the controller inside the right kick panel, and they are not to be had anywhere. If you really like the car and want to keep it, I would find a car with a manual system and buy it and pull the dash out of yours and switch over to the manual controls and related parts. You will live much happier and longer for biting the bullet and doing the changeover.

Or just sell the car and buy another one with a manual system.

When the old timer said "good luck", he meant what I just said.
 
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There are no parts available for these misersable and unreliable systems anymore, so trouble shooting will not do any good. The main culprit is the controller inside the right kick panel, and they are not to be had anywhere. If you really like the car and want to keep it, I would find a car with a manual system and buy it and pull the dash out of yours and switch over to the manual controls and related parts. You will live much happier and longer for biting the bullet and doing the changeover.

Or just sell the car and buy another one with a manual system.

When the old timer said "good luck", he meant what I just said.
Thank so much for the reply . I am pretty resourceful when required , I will make the defrosters operate with a 12v adjustable switch - have already had the defrosters working - next step is to find the correct mode actuator for floor heat and fabricate a cable pull for heat - the hell with the a/c . I've never had a/c in any of my toys anyhow ! I'm just going to drive the wheels off it ! Thanks again .
 
That is probably your best bet. Those Auto Temp systems were a PITA when you had the diagnostic tools & parts were still available. Nice looking NYer. What part of PA are you from?
 
I got an ATC-I system working in my old 68 NY. I had the luck the controller wasn't leaking. Main problem I had was that all the check valves that are in it all were defective and the push button control switch was leaking. There are 3 and 4 port check valves. You can simply make them yourself with aftermarket check valves together with 1 or more T-sprung. I used valves from bicycle tyres. After I replaced the push button control switch all actuators did what they should do and I re-soldered all connections in the control unit to make sure there were no bad connections.
After that I only needed to replace the thermostatic valve in the heating circuit, replace some AC hoses and the system worked fine.

If you don't need AC you can make the system working without it, with some bypasses/adjustments in the vacuum lines and a cable operated heater valve it can work. Check the vacuum circuit diagram and other info on the system and how to diagnose it at:
The technical service bulletins at The 1970 Hamtramck Registry "1968 PLYMOUTH, CHRYSLER & IMPERIAL TSBs Index" Page
The imperial club has a lot of info on the system
(Chrysler) Imperial Automatic Temperature Control Manual
Air Condtioning Repair Information For Your (Chrysler) Imperial
And of course the original MTSC instruction movies



I used a vacuum cleaner for vacuum source and a vacuum gauge to diagnose the system. (and a multi-meter)

Good luck!
 
I got an ATC-I system working in my old 68 NY. I had the luck the controller wasn't leaking. Main problem I had was that all the check valves that are in it all were defective and the push button control switch was leaking. There are 3 and 4 port check valves. You can simply make them yourself with aftermarket check valves together with 1 or more T-sprung. I used valves from bicycle tyres. After I replaced the push button control switch all actuators did what they should do and I re-soldered all connections in the control unit to make sure there were no bad connections.
After that I only needed to replace the thermostatic valve in the heating circuit, replace some AC hoses and the system worked fine.

If you don't need AC you can make the system working without it, with some bypasses/adjustments in the vacuum lines and a cable operated heater valve it can work. Check the vacuum circuit diagram and other info on the system and how to diagnose it at:
The technical service bulletins at The 1970 Hamtramck Registry "1968 PLYMOUTH, CHRYSLER & IMPERIAL TSBs Index" Page
The imperial club has a lot of info on the system
(Chrysler) Imperial Automatic Temperature Control Manual
Air Condtioning Repair Information For Your (Chrysler) Imperial
And of course the original MTSC instruction movies



I used a vacuum cleaner for vacuum source and a vacuum gauge to diagnose the system. (and a multi-meter)

Good luck!

thank you very much !
 
Can someone please tell me its function(s) and why?
Thank you.
It's in the first movie in my post above, starting at 5:25 the function of the water valve and the thermostat is explained. I can't explain it better then that but I'll try....
The amount of vacuum in the control vacuum circuit determines the basic state of the system, high vacuum is high heat (Hi DEF) and low vacuum is MAX COOL. The thermostatic valve regulates the heater valve with this signal together with the actual temperature of the air in the system. For example, high heat requested with cold air coming out of the system will open the water valve further than if the air coming out of the system was already hot.
 
update on the new Yorker I now have all modes - defrost/heat etc.. I even have temp change... no blower motor unless hot wired.... so I wired in a 12 volt adjustable switch with circuit board . im thrilled !
 
Please share how you got this far!
well...... after checking all electrical connections , vacuum hoses and routing of said hoses etc... I went to the blower motor and applied B+ to the blower and continued the diagnosis by going around the auto air systems control of the blower . after confirming all modes worked properly I ordered and installed the self contained switch WA LA ! IT WORKS !
 
I'm glad that you figured out a means to make it work. It's a great looking car. I've got a few things to tend to then we'll have to get together at some point. My car will make yours look even better.
 
well...... after checking all electrical connections , vacuum hoses and routing of said hoses etc... I went to the blower motor and applied B+ to the blower and continued the diagnosis by going around the auto air systems control of the blower . after confirming all modes worked properly I ordered and installed the self contained switch WA LA ! IT WORKS !
Please share info on the switch and source to purchase !! Thanks
 
Very interesting. My 65 Newport has manual controls and a 4-button pneumo-elec switch (no factory AC), but my 1984 M-B has an ATC that people say is based on an earlier Chrysler system. I now see the similarities. The M-B has more electrical drives (electric servo heater valve), 6 speed blower relay box, but I see how they descended from the Chrysler ATC. But, don't consider leveraging M-B parts because that climate control is also famously unreliable. Simple manual controls work fine and are preferred. I never understand the sense of adjusting a temperature setpoint vs just adjusting "more or less heat (or AC)". With ATC (our 2002 T&C), people just bugger with the setpoint anyway since they want it warmer initially until they get too hot. For those who can't fix it, you might re-rig it so your dash controls just affect the final control drives, eliminating the temperature sensor feedbacks.
 
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