Looking for suggestions 72 Imperial

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Hello Everyone! Im at the point now with my Imp where my next big challenge is gonna be HVAC. As far as I know nothing currently works. The blower motor won't kick on, I'm pretty sure the heater core leaks (it was looped when I got the car) the auto temp ii servo is cracked. and the AC system is empty. How should I approach? I would like to keep the original r-12 AC/auto temp system if possible. But I'm scared it may turn into an even bigger money pit. Ive priced it out to convert to an r-134 system would be around $900. does that sound like the way to go? if I do convert to r-134 would the auto temp still work properly? assuming I got a rebuilt servo of course.



-Thanks
Josh.
 
Hello Everyone! Im at the point now with my Imp where my next big challenge is gonna be HVAC. As far as I know nothing currently works. The blower motor won't kick on, I'm pretty sure the heater core leaks (it was looped when I got the car) the auto temp ii servo is cracked. and the AC system is empty. How should I approach? I would like to keep the original r-12 AC/auto temp system if possible. But I'm scared it may turn into an even bigger money pit. Ive priced it out to convert to an r-134 system would be around $900. does that sound like the way to go? if I do convert to r-134 would the auto temp still work properly? assuming I got a rebuilt servo of course.



-Thanks
Josh.

@saforwardlook
 
To check your heater core, plug one of the disconnected hoses coming from the core and on the other connect a miti vac pump to draw a vacuum. get it up to 15 IN HG of vacuum. Let it sit and see if it holds.
The main reason that heater hoses get looped on Autotemp cars is because the Autotemp servo leaks.
 
If an a/c system originally designed for R-12 can work on R-134a, no real reason that your AT-II system can't do the same. I know there are some differing orientations on keeping R-12 or converting, btaim.

As to conversion and the items used, that can depend upon how original you desire to keep the vehicle and/or how stealthy you can install things like a mass-flow condenser and make it not look aftermarket. The receiver-drier can be rebuilt, I believe, so that can be kept stock looking.

From the performance of the factory a/c system in our '72 Newport Royal, the system is apparently not up to the task of the added interior space of the Fuselage Chryslers, although the smaller volume of my '70 Monaco DH43 seems to work a bit better, but not as well as the system in our '66 Newport Town Sedan. In changing parts, it would be a good time for a condenser size upgrade and possibly a Sanden compressor too?

@safirwardlook can comment on these things and sourcing of the parts needed, if replacing just the OEM parts, I suspect.

Just some thoughts,
CBODY67
 
Biggest thing with r12 to 134a is do NOT FLUSH the a/c system, use 20% less 134a, look for major leaks from there and test for operation. It's just a slow process. My 73 new yorker I've found the blower switch fried when I pulled the cluster, along with other wiring issues and broken pins on the circuit board, hvac controls all the plastic broken apart, money's tight so I have to just wait.

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Biggest thing with r12 to 134a is do NOT FLUSH the a/c system, use 20% less 134a, look for major leaks from there and test for operation. It's just a slow process. My 73 new yorker I've found the blower switch fried when I pulled the cluster, along with other wiring issues and broken pins on the circuit board, hvac controls all the plastic broken apart, money's tight so I have to just wait.

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Good advice. For me, I have had the best success in charging R-134a systems using pressures.
 
The original recommendations on "gas" was to start with 20% less gas than the R-12 spec, then slowly add gas until cooling got the coldest and then stop adding gas. The usual result was approx 90% of the R-12 spec charge. An IR heat gun can work for this. R-134a is more sensitive to over-charge than R-12 is. Whatever works!

CBODY67
 
I too would suggest you read through all the discussions on this subject that have occurred in the past. Most of my opinions having worked on a few of these systems is to first make sure you have a good RV2 Chrysler compressor in the first place that doesn't have a lot of miles on it or an NOS one if you can still find one. Perhaps the most costly issue is trying to have one rebuilt since it seems no one makes a really good rebuild kit based on the number of failures I have heard about with the only rebuild kit I am aware of from a Florida source.

I prefer going with R12 since the few conversions I have heard about have not been successful with 134 for a number of reasons either because of not achieving suitable low temperatures unless you use a non-original temp sensing switch closer to the evaporator and premature compressor failures. There are only 2 suppliers of the really good Autotemp II newly remanufactured controllers and either one of them is fine. I also believe you would be doing yourself a favor and work with an A/C shop that is familiar with working on old cars that won't let you down. I am grateful to have a really good shop available near me in Ontario, California. AC Global makes good heater cores, evaporators, and condensers and have worked with Mr. Heater Box out of Canada that also rebuilds your control boxes under the lower right hand side of the dash assembly. That Canadian company is also first rate.

The only other option if you can't find an NOS RV2 compressor is maybe a rebuilt perhaps from someone who has really good feedback from a good number of sales he has made with 100% feedback - here is just one I found on Ebay today with 14 rebuilt RV2 compressors sold - and still 100% feedback:

RV2 A/C COMPRESSOR WITH CLUTCH FITS MANY CHRYSLER AND DODGE WITH DRIER AND VALVE | eBay

Best wishes and none of this is inexpensive...................
 
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The original recommendations on "gas" was to start with 20% less gas than the R-12 spec, then slowly add gas until cooling got the coldest and then stop adding gas. The usual result was approx 90% of the R-12 spec charge. An IR heat gun can work for this. R-134a is more sensitive to over-charge than R-12 is. Whatever works!

I too would suggest you read through all the discussions on this subject that have occurred in the past. Most of my opinions having worked on a few of these systems is to first make sure you have a good RV2 Chrysler compressor in the first place that doesn't have a lot of miles on it or an NOS one if you can still find one. Perhaps the most costly issue is trying to have one rebuilt since it seems no one makes a really good rebuild kit based on the number of failures I have heard about with the only rebuild kit I am aware of from a Florida source.

I prefer going with R12 since the few conversions I have heard about have not been successful with 134 for a number of reasons either because of not achieving suitable low temperatures unless you use a non-original temp sensing switch closer to the evaporator and premature compressor failures. There are only 2 suppliers of the really good Autotemp II newly remanufactured controllers and either one of them is fine. I also believe you would be doing yourself a favor and work with an A/C shop that is familiar with working on old cars that won't let you down. I am grateful to have a really good shop available near me in Ontario, California. AC Global makes good heater cores, evaporators, and condensers and have worked with Mr. Heater Box out of Canada that also rebuilds your control boxes under the lower right hand side of the dash assembly. That Canadian company is also first rate.

The only other option if you can't find an NOS RV2 compressor is maybe a rebuilt perhaps from someone who has really good feedback from a good number of sales he has made with 100% feedback - here is just one I found on Ebay today with 14 rebuilt RV2 compressors sold - and still 100% feedback:

RV2 A/C COMPRESSOR WITH CLUTCH FITS MANY CHRYSLER AND DODGE WITH DRIER AND VALVE | eBay

Best wishes and none of this is inexpensive...................
Good steering input. The challenge is to find that shop. I’m more of a do it yourself guy, especially when I run into poor experience with a shop.
 
Hello Everyone! Im at the point now with my Imp where my next big challenge is gonna be HVAC. As far as I know nothing currently works. The blower motor won't kick on, I'm pretty sure the heater core leaks (it was looped when I got the car) the auto temp ii servo is cracked. and the AC system is empty. How should I approach? I would like to keep the original r-12 AC/auto temp system if possible. But I'm scared it may turn into an even bigger money pit. Ive priced it out to convert to an r-134 system would be around $900. does that sound like the way to go? if I do convert to r-134 would the auto temp still work properly? assuming I got a rebuilt servo of course.



-Thanks
Josh.
I’m running r134a in my ‘72 Imp w/Auto Temp II, with no problems. I initially had to replace the servo, amp, pushbutton switch, compressor and amp connector.
 
I too would suggest you read through all the discussions on this subject that have occurred in the past. Most of my opinions having worked on a few of these systems is to first make sure you have a good RV2 Chrysler compressor in the first place that doesn't have a lot of miles on it or an NOS one if you can still find one. Perhaps the most costly issue is trying to have one rebuilt since it seems no one makes a really good rebuild kit based on the number of failures I have heard about with the only rebuild kit I am aware of from a Florida source.

I prefer going with R12 since the few conversions I have heard about have not been successful with 134 for a number of reasons either because of not achieving suitable low temperatures unless you use a non-original temp sensing switch closer to the evaporator and premature compressor failures. There are only 2 suppliers of the really good Autotemp II newly remanufactured controllers and either one of them is fine. I also believe you would be doing yourself a favor and work with an A/C shop that is familiar with working on old cars that won't let you down. I am grateful to have a really good shop available near me in Ontario, California. AC Global makes good heater cores, evaporators, and condensers and have worked with Mr. Heater Box out of Canada that also rebuilds your control boxes under the lower right hand side of the dash assembly. That Canadian company is also first rate.

The only other option if you can't find an NOS RV2 compressor is maybe a rebuilt perhaps from someone who has really good feedback from a good number of sales he has made with 100% feedback - here is just one I found on Ebay today with 14 rebuilt RV2 compressors sold - and still 100% feedback:

RV2 A/C COMPRESSOR WITH CLUTCH FITS MANY CHRYSLER AND DODGE WITH DRIER AND VALVE | eBay

Best wishes and none of this is inexpensive...................
saforwardlook what exactly are the problems with the florida kits? are these the Polar Bear ones? been trying to do a load of research prior to rebuilding mine and this is my first time hearing this...got any links?
 
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saforwardlook what exactly are the problems with the florida kits? are these the Polar Bear ones? been trying to do a load of research prior to rebuilding mine and this is my first time hearing this...got any links?

I just recall that @MonacoBlue on this site had the Florida company rebuild the compressor on his Monaco Wagon and he had plenty of problems with it but I am not sure specifically what they all were after a couple years now, so you might contact him. Others have said their rebuilds do not contain the quality components like the original ones from Chrysler did. I personally would go the route I suggested earlier via Ebay with a seller with 100% feedback I noted above and maybe contact him to find out which rebuild kit he uses and his assessment of how his rebuilds compare to others such as Classic Auto Air out of Florida.
 
ok not looking to have anyone build mine...originally sourced gasket sets from Polar Bear in Florida (i dont believe that they rebuild anything, they just sell gaskets)after Classic Industries and Original Air discontinued theirs...since then came up with NOS stuff that came with the pistons and crank so was planning on using those anyway...just didnt know if there were issues with the first ones i found
 
I tried twice to get mine rebuilt with Classic in Fla. Did not have good results either time and used a very skilled installer in my end. I eventually went with a modern upgrade. I can tell it puts less load/ drag on the engine but it does not cool as effectively.
 
ok not looking to have anyone build mine...originally sourced gasket sets from Polar Bear in Florida (i dont believe that they rebuild anything, they just sell gaskets)after Classic Industries and Original Air discontinued theirs...since then came up with NOS stuff that came with the pistons and crank so was planning on using those anyway...just didnt know if there were issues with the first ones i found
Good luck. I have a 400 2bbl
set up on a 73 Dodge wagon with third row overhead. Some added complexity.
 
I got the runaround with them when I was trying to get mine rebuilt. Every time I’d call to get a status I’d talk to someone new and they told me they would get right on it. I think they had high staffing turnover. This was 2020 timeframe during the middle of COVID. The rebuilt product was rattling from the get go. I spent (lost) hundreds there, for nothing. It was a very disappointing experience from a company from which I expected first class service and product.
 
unfortunately they are another reputable company that has been around forever that retired and sold out to an investment group....same ones that bought Master Power brakes i believe...things don't appear to be improving
 
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