Restoring A/C

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CGWelding

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I haven't known any different with this truck and am not sure what A/C parts I'm missing. I'm not sure the conditions the previous owner faced when they decided to disconnect everything.
There's no compressor or mount and no condensoror lines.
Surely it can't be as simple as finding these parts.
Heat kicks like a mule though BTW.
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NLD79K10

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Looks like you basically have nothing except for the evaporator and the receiver/dryer left in there and maybe the pressure switch on the receiver, but that is not visible from this angle. It's difficult to tell from the picture but it also looks like the wiring for the compressor isn't there anymore either, you should be able to find a thick light green wire coming from the HVAC control panel in the cab going to the throttle solenoid and pressure switch and a dark green wire coming from the pressure switch to a flat two-pin connector at the end together with a black ground wire that switch the compressor clutch.

I'm currently in the process of gathering together the bits needed to restore my old A/C system as well, I have just a few more parts of this puzzle as I still have the wiring and the line going from the evaporator to the condenser and half of the brackets. I bought most of the parts except for the brackets and a compressor so far and I am considering to replace the old condenser and evaporator as well so I stand a chance of starting off the summer with a working and gastight system.
 

CGWelding

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Looks like you basically have nothing except for the evaporator and the receiver/dryer left in there and maybe the pressure switch on the receiver, but that is not visible from this angle. It's difficult to tell from the picture but it also looks like the wiring for the compressor isn't there anymore either, you should be able to find a thick light green wire coming from the HVAC control panel in the cab going to the throttle solenoid and pressure switch and a dark green wire coming from the pressure switch to a flat two-pin connector at the end together with a black ground wire that switch the compressor clutch.

I'm currently in the process of gathering together the bits needed to restore my old A/C system as well, I have just a few more parts of this puzzle as I still have the wiring and the line going from the evaporator to the condenser and half of the brackets. I bought most of the parts except for the brackets and a compressor so far and I am considering to replace the old condenser and evaporator as well so I stand a chance of starting off the summer with a working and gastight system.
Thanks this gives me at least an idea what it would take.
 

Trucksareforwork

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Getting A/c to run is a rewarding project. You have a lot of stuff missing. The vacuum lines to the vacuum canister on your passenger side firewall are missing and easy to replace, but you’ll also have to check all your vacuum lines inside the cab. Since you said the heat works well, that probably means you have vacuum somehow because iirc the system defaults to defrost if no vac.

You can use the old condenser and evaporators if you buy a flush kit and clean them out (assuming they weren’t the problem). You have to buy a new receiver dryer canister because they go bad when open to air.

Lines can be fabbed pretty easily, the ac bracket can be found at most junkyards. The expensive part might be the actual compressor though they are a dime a dozen used and remanufactured as well. Conventional wisdom is to go with a sanden style compressor.
 

NLD79K10

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Lines can be fabbed pretty easily, the ac bracket can be found at most junkyards. The expensive part might be the actual compressor though they are a dime a dozen used and remanufactured as well. Conventional wisdom is to go with a sanden style compressor.

Agreed, the Sanden style compressors are a lot less likely to self-destruct than the A6 and R4 ones GM originally installed in these trucks, even brand new ones don't seem to be all that reliable in the long run. IIRC LMC do a Sanden style compressor with the correct fittings for the original hoses.
 

Rickf

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There's also a 12v electric compressor option.
 

Sad Sack

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There's also a 12v electric compressor option.
What did you find? The ones I’ve seen are high wattage, 900 watts mofos for around $700
 

k5wolff

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Currently doing the same. After lot's of debate and research I removed the R-4 and am using a sanden. amazon has a "real" one for $240. Also used the Vintage air bracket that also replaces the clumsy power steering bracket. It's about $170 from summit. Looks like the belt is going to be 58" long.
There is a perfect replacement condenser coil also on amazon Universal Air Conditioner CN 3642PFC A/C Condenser.
You can just tilt the radiator forward to install.
Still working on a few other things but still need hoses (have to get a local shop to fab up some). Cold hose is also a cool online hose building sight if needed.
Might also get rid of the accumulator with the lower bend to clean up the area. Some guys have used the one that comes straight out to get the suction line above everything. Should also keep the refrig oil from pooling so low.
Still progressing...
 

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