A/C Upgrade / Restoration. Any Tips?

Given the amount of disassembly I think trying to have the car ready to show in May is possibly over-ambitious.

Don't rush things. You will regret it. Take your time, do it right. There will be other shows.
 
Just FYI, there are new heater cores available for A/C equipped cars. Search for 1968 Mopar dual heater cores for c bodies. The
search will bring up cores on E-Bay, Original Air, Mopar Mall etc. the evaporator and heater core are combined in one unit so they are pricey, I’ve seen them go for $340 to $465. Maybe you can have it recored for less? I have seen that suggested on this forum in other threads.
Heater and evaporator cores are available. I just did my box, actually started last July and finished it in Nov. (Don't ask - life got in the way.) I found two sources for heater cores. One bolts up beautifully but the coolant connections are wrong the other the mounting plate needs massaged to mount, but the coolant connections are correct.

You want this one - GOOD HEATER CORE These guys also offer an EVAPORATOR CORE, but I don't have an experience as to whether it fits good or not.

Stay away from this one, coolant lines don't fit. BAD HEATER CORE

Mr Heaterbox in Harrow ON Canada can redo that AC Heater assembly to new. Sometimes it's best just to let the experts deal with an assembly that you can just bolt in and not worry about.

mr heaterbox AC restoration - Google Search

Basic AC is not too complicated, but it's quite fiddly.
This guy is incredibly knowledgeable and helpful even when he isn't making a buck off of you. I cannot tell you how many times Brian and I emailed during my rebuild.

He told me to buy one of these as well because they leak after sitting H VALVE
Given the amount of disassembly I think trying to have the car ready to show in May is possibly over-ambitious.

Don't rush things. You will regret it. Take your time, do it right. There will be other shows.
Isaiah, you're young... ^^^ listen to this wisdom. Hang in there you will make it to the finish line.

Big_John linked my rebuild thread to this. You use the AC mounting bracket that I used you don't have to mess with your power steering pump. If you install a new evaporator or condenser, but don't finish the system make sure they are sealed from the atmosphere.

I had my hoses crimped at a garage that services semis. You have to make sure that your hose ends are oriented in the correct directions prior to crimping because there is no twisting to hose to accommodate for miss alignment.
 
Lot of good tips. Here is my thread: 66 Monaco Wagon A/C Resurrection
I did an underhood update to R134 including Sanden, new condenser, dryer, lines, etc. The Sanden 715 variant is a good choice for these large cars. My car has dual factory air and I was lucky that both evaporators and the heater core were good and reuseable. Rebuilding your evaporator should be doable but costly. Good luck!

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Heater and evaporator cores are available. I just did my box, actually started last July and finished it in Nov. (Don't ask - life got in the way.) I found two sources for heater cores. One bolts up beautifully but the coolant connections are wrong the other the mounting plate needs massaged to mount, but the coolant connections are correct.

You want this one - GOOD HEATER CORE These guys also offer an EVAPORATOR CORE, but I don't have an experience as to whether it fits good or not.

Stay away from this one, coolant lines don't fit. BAD HEATER CORE


This guy is incredibly knowledgeable and helpful even when he isn't making a buck off of you. I cannot tell you how many times Brian and I emailed during my rebuild.

He told me to buy one of these as well because they leak after sitting H VALVE

Isaiah, you're young... ^^^ listen to this wisdom. Hang in there you will make it to the finish line.

Big_John linked my rebuild thread to this. You use the AC mounting bracket that I used you don't have to mess with your power steering pump. If you install a new evaporator or condenser, but don't finish the system make sure they are sealed from the atmosphere.

I had my hoses crimped at a garage that services semis. You have to make sure that your hose ends are oriented in the correct directions prior to crimping because there is no twisting to hose to accommodate for miss alignment.

Thanks for this valuable knowledge and advice! I will look into purchasing everything you listed. Unfortunately it seems like they’re out of the AC/Heater core as it says unavailable :/

Lot of good tips. Here is my thread: 66 Monaco Wagon A/C Resurrection
I did an underhood update to R134 including Sanden, new condenser, dryer, lines, etc. The Sanden 715 variant is a good choice for these large cars. My car has dual factory air and I was lucky that both evaporators and the heater core were good and reuseable. Rebuilding your evaporator should be doable but costly. Good luck!

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Love this setup!!! Looks so clean, I will check your thread out, thanks!!!

Given the amount of disassembly I think trying to have the car ready to show in May is possibly over-ambitious.

Don't rush things. You will regret it. Take your time, do it right. There will be other shows.

You’re right, it is cutting it pretty close! Just a nail biter lol. If I miss it there’ll be more shows like you said:) 2 years ago I bought the car thinking I’d get it to run and clean it up and take it to the same show. Guess when it finally makes it it’ll at least get lots of attention! :thumbsup:
 
I hear you - ambition is often tempered by reality.

I have embarked on a resurrection of my 66 Dodge Monaco 440 4 speed car which was a running driving perfectly fine car until I had a very minor fender-bender with it (not my fault). I got some decent insurance money and wanted to put it and a bit more dollars towards a cosmetic fix up - and of course once I started taking things apart I found more and more issues that I just could not ignore. As good as it looked this car was turning the corner and needed to be saved.

It has turned into a complete restoration that is now going on 8 years... thankfully I knew this was coming well before what I had hoped was going to be the cosmetic interim fix up, and have been collecting parts and assemblies for it for decades.

Part of the reality for me is finances. Covid-19 has rendered my music income next to nil for the last two-and-a-half years...
 
I see that you purchased a 3502126 A/C switch. It is correct for 72-73 C body. You will need an on/off switch in the wire to your compressor with that MoPar switch, otherwise the compressor will be on all the time the engine is running. 72-73s had a micro switch installed on the A/C heat control cable.
 
I see that you purchased a 3502126 A/C switch. It is correct for 72-73 C body. You will need an on/off switch in the wire to your compressor with that MoPar switch, otherwise the compressor will be on all the time the engine is running. 72-73s had a micro switch installed on the A/C heat control cable.
Oh snap! I purchased it cause it said “68-74 w/ 5 buttons.” Listing stated: That it has 7 vacuum hose nipples and 5 electrical terminals. Said it replaces Replaces switches 3431020, 2820487, 3895033, 3895790. Should’ve paid more attention lol… what is the correct one I should look for?
 
Oh snap! I purchased it cause it said “68-74 w/ 5 buttons.” Listing stated: That it has 7 vacuum hose nipples and 5 electrical terminals. Said it replaces Replaces switches 3431020, 2820487, 3895033, 3895790. Should’ve paid more attention lol… what is the correct one I should look for?
That info was incorrect. That was from me almost 15 years ago. I had the supersession chain for this switch wrong. It has been used as 'fact' ever since.
3895790 is the most common MoPar #. Used to be able to get them through NAPA stores. Should be $75 +- If you go on FeEBay, just pick the least expensive NEW one.
 
That info was incorrect. That was from me almost 15 years ago. I had the supersession chain for this switch wrong. It has been used as 'fact' ever since.
3895790 is the most common MoPar #. Used to be able to get them through NAPA stores. Should be $75 +- If you go on FeEBay, just pick the least expensive NEW one.

Just to confirm then, 3895790 is the correct one for a 68 C-Body?
 
Just to confirm then, 3895790 is the correct one for a 68 C-Body?
From what I understand it is. It's been at least 15 years since I've done 'hands on' work on a '67 or '68 C body, so you should verify the info. The other guys here should know. That is for NON ATC versions. 3431020 and 3895033 were also good numbers. Just not the 3502126.
 
Pulled the heater box today!

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Does anyone know what these are called, and where I can get them new?

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If they can even be found new? Thanks! I have a rebuild kit from DMT coming in.
 
I also bought a new AC / Heater core, kudos to @live4theking pointing me in the right direction of a good unit. Came in today, still in the box. Don’t plan to open it until I’m absolutely ready to install!
 
Those things are called vacuum actuators. They can be found on eBay fairly often. I am not sure if they're rebuildble, but others may know.
 
So I pulled out the dash to the New Yorker leaving the heater box exposed!

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I am in the best position ever to remove this box and do a refresh on it. I want to modernize this system and add on a Sanden SD7H15 compressor to the system.

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Scored this Heater / AC control switch on eBay earlier. As far as the box goes, what do I need to do to make sure this thing is good to go once I re assemble everything? I’d hate to have the thing installed and find out it’s not working properly. Is there anything that can be upgraded or retrofitted in there? I don’t believe there are new heater cores available for the factory AC 68.

Are there any detailed threads on this here on FCBO? I couldn’t find much when I tried to do a quick search…

ALSO!!! Can anyone point me out to where I can find the rubber seals / gasket that go on here the heater hose in / out goes on the firewall? Mine are thrashed.

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When I did the same thing (maybe 10 yrs ago), I just bought a heater box gasket kit, tested the vacuum actuator (don't recall if there was one or two), replaced vacuum lines and re-installed it. It's amazing how much better it worked with just the gaskets. After I did that, the blower motor died, so you might consider being pre-emptive and just replacing that while you have it out. The sanden compressor and conversion to a more modern refrigerant is good too.
 
I see that you purchased a 3502126 A/C switch. It is correct for 72-73 C body. You will need an on/off switch in the wire to your compressor with that MoPar switch, otherwise the compressor will be on all the time the engine is running. 72-73s had a micro switch installed on the A/C heat control cable.
Devin: checking on eBay, I see both 3502126A and 3502126B -- what is the difference between the two?

That info was incorrect. That was from me almost 15 years ago. I had the supersession chain for this switch wrong. It has been used as 'fact' ever since.
3895790 is the most common MoPar #. Used to be able to get them through NAPA stores. Should be $75 +- If you go on FeEBay, just pick the least expensive NEW one.
Would 3895790 be a replacement for both 3502126A and 3502126B? I am asking for my 1972 NYB with manual A/C.
 
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Devin: checking on eBay, I see both 3502126A and 3502126B -- what is the difference between the two? I am asking for my 1972 NYB with manual A/C.
No difference. Could have just been different vendors to Chrysler
 
No difference. Could have just been different vendors to Chrysler
Thank you!
3895790 is the most common MoPar #. Used to be able to get them through NAPA stores. Should be $75 +- If you go on FeEBay, just pick the least expensive NEW one.
Would P/N 3895790 be a replacement for both 3502126A and 3502126B? I am asking for my 1972 NYB with manual A/C.
 
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