73 AC

pickman

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Thank everyone that has sent me tags and threads on this subject.

My approach is to pull a vacuum n the evaporator tubes sticking thru the firewall - pending I get adapter fittings. If this holds I will then proceed.

My plan is to use original R12 refrigerant and a new original OEM filter drier.

Use the original condenser (initially)

Per all the feedback it looks like a Sanden SD-510HD compressor New - unless there is another better choice??

The only unknown is the compressor mounting bracket - I see an M5 is recommended I don't know the PN - unless there is another better choice?

New hoses with fittings that fit the system.

I will use the original fan.

I can upgrade the condenser to parallel flow with a new fan later if required.

R134 and R12 are similar in pressure points however have different boiling points. R134 actually extracts more heat per pound but to achieve this a larger condenser coil with more air flow is required. The TXV probably needs to be revised for 134 to achieve balance. So all in all I'll stick with R12 if possible save a few$$ and see what performance is achieved.

Any advice on the mounting bracket PN and or compressor is much appreciated.
 

Stevehose

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I would strongly suggest putting in the parallel flow condenser now and use with the original fan then you’ll never have to go back and change it and it’s vastly superior to the original unit. And cheap.
 

pickman

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I would strongly suggest putting in the parallel flow condenser now and use with the original fan then you’ll never have to go back and change it and it’s vastly superior to the original unit. And cheap.
Sir,

what model and make would you suggest?
 

pickman

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There was a reply some posts ago regarding AC fittings that can be purchased that adapt the high and low pressure tubes at the firewall (from the evaporator)so I can use a vacuum pump to pull vacuum.

Any help? Please!
 

pickman

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It's all in this thread:

https://e9coupe.com/forum/threads/air-conditioning-upgrade-photos-details.9633

I believe others have squeezed a larger one in, not sure if larger matters because it's efficiency now is better than the dash can keep up with.

You have done a great job! My rubber compressor bracket bushings are gone can you recommend a replacement? Also not sure on the copper washers between the evaporator to tube fittings and where to get these conical washers?
Also do you recommend removing the water pump to effect this conversion?

Thanks again!
 

Stevehose

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What bracket are you using? You'll need copper washers for evap. You shouldnt have to remve the water pump, once the radiator is out there's plenty of room in there. But if yu don't know how old the pump is change it. Cheap insurance.
 

pickman

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What bracket are you using? You'll need copper washers for evap. You shouldn't have to remove the water pump, once the radiator is out there's plenty of room in there. But if yu don't know how old the pump is change it. Cheap insurance.
I bought the same bracket you show from Johnjoy, I have both the original York 1973 compressor bracket and a newer M30 -528 compressor mounting bracket.
 

pickman

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What bracket are you using? You'll need copper washers for evap. You shouldnt have to remve the water pump, once the radiator is out there's plenty of room in there. But if yu don't know how old the pump is change it. Cheap insurance.

Please review the attched photo of the bushing I am missing - any Ideas?
 

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Stevehose

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Hmmm not offhand, perhaps remove them and measure then try a place like McMaster Carr to see if they have something. Perhaps others here have ideas.
 

HB Chris

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That is why using the York bracket should be your last resort. I have been told you can take a poly alternator bushing and turn them down on a lathe to the right diameter. Mesa Performance offered this suggestion.
 

pickman

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Well Gentlemen I have a 528i bracket see attached - no bushings and per the forum not too much to adapt the Sanden compressor to the bracket - maybe a better way to go?
 

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aearch

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ac1.jpg
AFTER LOOKING AT MY SYSTEM I USED THE STOCK OEM M5 COMPRESSOR
FOR THE S38B36 IT WORKS WITH THAT MOUNT WITH A TOP BRACKET
MAKE BOTTOM AND TOP BRACKETS FROM THE EXTRA PARTS

diag_6y5.png
 
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