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74 tii modern underhood AC install


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I thought I would chronicle the installation of modern under-hood components in my 74 Tii. I have had the car about a two weeks now, and it came with all Behr original components installed but not working. I have converted every other classic car I have had with modern compressor, evaporator, and R134, so I have a decent amount of experience. I bought the following from coldhose, which is about 2 hrs from my house:

Sanden SD7H15 compressor ($235)

York to Sanden compressor adapter ($40)

Hose and dryer kit, including switch ($100)

10X18 condenser and brackets($62)

#6 and #10 flare to o-ring adapters

The Sanden fits perfectly with the adapter. I need slightly longer bolts for my final installation, but the adapter just bolts to the original compressor bracket. To get the compressor aligned with the tii pulley, I needed to run the bolt through the adapter plate, then add a nut, then put the compressor through. This pushed it back 1/4".



After temporarily unbolting the horn, the condenser goes in to the hole, and fit perfectly between the uprights. I made two simple brackets utilizing the holes for the horn on each side to hold the condenser. It is very solid when attached.








Cold hose sells some cheap pusher fans, but I have always had the best luck with spal, so I bought a 10" pusher fan. Made a simple sheet metal bracket for the bottom holes. 



That is it for today. I need to change the front main seal before I install the compressor for the final time and figure out belt length. 

More tomorrow.



Edited by xavier296
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Finished more today. Belt and original tensioner are installed.


Condenser and fan combo are installed.


Dryer is installed. I had two screw holes in my core support for the dryer, and the cold hose dryer bracket lined up perfectly with the existing holes. I have started mocking up hoses, so I'll pull out the crimper and get them done today.



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Nice installation. I’m about where you left off, sans compressor. Some have said the Chinese clones are just fine vs. a real Sanden. Your thoughts? Also, you might paint your hinges black before installing the grills,  BMW thought that was a good idea to hide behind the grill, lol.

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  • 2 weeks later...

Well, she is fighting me. I was able to remove the old "made in west Germany" expansion valve, despite the tightened to oblivion connections. R134a expansion valve installed, then whole unit reinstalled.


The worst part was cleaning the gross squirrel cages. So much dust...


Determined the motor was wired backwards when I removed it, so it was blowing, but not very well. Switching the wires added a lot of air movement.


After getting everything installed and hoses made, she won't hold a vacuum. I found one leak in a hose from an improper crimp, and I think I found the other at the new expansion valve connections. I guess I didn't tighten them enough. Oh well, I'll keep at it.




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  • 2 months later...

After a million delays not related to the AC, I have finally been driving Henrik to work here in Tampa for the last few days. The AC blows very cold, with sub freezing temps possible (Thermometer showed 29 degrees). My drive is all city, and only about 5 miles each way, but I am sure that you would have to turn it down if cruising down the highway for any amount of time.


Not a huge amount of air flow, but I knew that going in. 


Sat in traffic going home yesterday (First time I have seen traffic on the base since COVID started), and didn't seem to mind the 25 minutes of idling with the AC going in 87 degree heat. 

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