SAAC Forum

The Cars => 1969-1970 Shelby GT350/500 => Topic started by: Don Johnston on September 15, 2022, 11:38:12 PM

Title: 1970 GT500Needs A/C replacement Parts
Post by: Don Johnston on September 15, 2022, 11:38:12 PM
Doing this for an elderly owner of #2732 here in Hawaii.  The GT500 was sold at Gaplin Ford in Sepulveda, CA.  Build date 5/26/69.  He needs the a/c repaired and is working on conversion from R12 to R134a coolant.  What compressor and evaporator does he need to order?  Hoses or other items?  He will retain the original pieces for the next owner.  His a/c repair guys say there are two possible different compressor units depending on date of build.(?????).  Any input would be appreciated as to what to parts to get and recommended source(s).  Shipping incorrect parts in and back  from Hawaii gets expensive, if not annoying.

Thank you. 8)
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: tesgt350 on September 16, 2022, 07:23:44 AM
I thought you just had to change out the Seals to convert it and NOT any of the Components.
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: Lincoln tech on September 16, 2022, 08:04:05 AM
Just replace the faulty part and recharge with 134A , no need to replace the whole system, don't forget === you can still buy R12 .
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: shelbymann1970 on September 16, 2022, 09:25:40 AM
You may want to read this. https://aa1car.com/library/retrofit.htm
I'd stay with R12 when possible.
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: shelbydoug on September 16, 2022, 09:41:10 AM
You do not need to change anything to run the original system on R134a.

Just charge it with the 134.

The only difference that you are going to see is that measurable temperature of the cool air blowing out of the registers with 12 could be as low as about 34 degrees and the 134 about 40 degrees.

Unless you are in Las Vegas or Pheonix in the middle of the summer, you will never miss that.


The 134 "charging kit" is going to come with adapters for your compressors valves. Those are only necessary initially to adapt the 134 connectors. Once you are done, you can remove them and just save them for when you need to top the system off again.

Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: FL SAAC on September 16, 2022, 10:33:58 AM
If you dont mind not being completely original

You have the option of installing a sanden compressor they seem more efficient
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: Bob Gaines on September 16, 2022, 10:39:34 AM
Quote from: Don Johnston on September 15, 2022, 11:38:12 PM
Doing this for an elderly owner of #2732 here in Hawaii.  The GT500 was sold at Gaplin Ford in Sepulveda, CA.  Build date 5/26/69.  He needs the a/c repaired and is working on conversion from R12 to R134a coolant.  What compressor and evaporator does he need to order?  Hoses or other items?  He will retain the original pieces for the next owner.  His a/c repair guys say there are two possible different compressor units depending on date of build.(?????).  Any input would be appreciated as to what to parts to get and recommended source(s).  Shipping incorrect parts in and back  from Hawaii gets expensive, if not annoying.

Thank you. 8)
All 69/70 Shelby's got the same Tecumseh compressor. remember 70 Shelby's were built in 69 production.
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: GT350DAVE on September 16, 2022, 11:35:38 AM
We just restored the AC system in my 67 GT 350. I had Original Air out of Florida rebuild the original compressor and purchased lines and other components from them. They were horrible to deal with. They first said they could clean the original lines and then lost them. The next story was they couldn't clean them anyway. We had to return the clutch 3 times and thr compressor twice. In hind site, I believe the clutch they rebuilt, not the compressor was always the issue but their attitude was always it was always our fault. We ended up using a new clutch.The water valve came back from them painted, not plated with the original 1967 O ring still installed. It would have never worked property.
We used R12. It is still around as is an R12 replacement which is similar but very expensive.
The end result however is ice cold air. The temperature coming out of the vents is 36 degrees. Another car I am familiar with was converted to R134 and wasnt able to achieve anything near that temperature. We didn't do the work on that car so there are other things like a faulty water valve that can effect temperature but this is my experience.
Dave
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: Bob Gaines on September 16, 2022, 12:33:55 PM
Unfortunately I think Original Air out of Florida is the only game in town. If someone has experience with another please post.
Title: Re: 1970 GT500Needs A/C replacement Parts
Post by: shelbydoug on September 16, 2022, 01:07:24 PM
Quote from: GT350DAVE on September 16, 2022, 11:35:38 AM
We just restored the AC system in my 67 GT 350. I had Original Air out of Florida rebuild the original compressor and purchased lines and other components from them. They were horrible to deal with. They first said they could clean the original lines and then lost them. The next story was they couldn't clean them anyway. We had to return the clutch 3 times and thr compressor twice. In hind site, I believe the clutch they rebuilt, not the compressor was always the issue but their attitude was always it was always our fault. We ended up using a new clutch.The water valve came back from them painted, not plated with the original 1967 O ring still installed. It would have never worked property.

I've done several and from experience can tell you that you can get the 134 under 40. Technically "they" say no, only 42.

Given the cost of r12 at $50 a can, it isn't worth the effort to use it.

The original compressor is very easy to rebuild and generally it isn't even a rebuild. More of a cleaning and some new o-rings.

The Florida guy is just a cranky old retired guy and his wife who charges handling on everything you buy. A 25 cent o-ring will cost you $25 to get it in your door.
We used R12. It is still around as is an R12 replacement which is similar but very expensive.
The end result however is ice cold air. The temperature coming out of the vents is 36 degrees. Another car I am familiar with was converted to R134 and wasnt able to achieve anything near that temperature. We didn't do the work on that car so there are other things like a faulty water valve that can effect temperature but this is my experience.
Dave