Really weird air conditioning problem

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fast 99

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First need flush fluid. Disconnect compressor, remove orifice tube. I don't measure the fluid. Just pour a cup or so in condenser and evaporator, using air hose blow it out. Do not use full pressure, especially on evaporator. Put a rag over the other outlet to avoid a mess and check for contaminates. Repeat until clean, flush hoses., replace drier. Remember there will not be any oil in the system at this point except compressor if that was re-used. Going this far recommend replacing the hoses and of course add correct AC oil spread throughout system.
 

Turbo4whl

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The second time when I took it out after the compressor locked up it was definitely clogged. I blew out the evap and condenser with air but was nervous to use flush stuff because I don't know if it will all come out with everything installed in the truck still.
Okay, you need to flush every part clean as @fast 99 stated. The compressor oil makes the inside of all the parts sticky. That in turn holds all the shredded compressor guts. Disconnect and flush each part with a solvent based cleaner. I know they sell spray cans with adapters to flush out trans coolers. The hoses may not like any solvent cleaners. That is why you may want to replace them also as stated.

I could go and on and on about aftermarket and (rebuilt) parts.... I'll shut up...
 

louu

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First need flush fluid. Disconnect compressor, remove orifice tube. I don't measure the fluid. Just pour a cup or so in condenser and evaporator, using air hose blow it out. Do not use full pressure, especially on evaporator. Put a rag over the other outlet to avoid a mess and check for contaminates. Repeat until clean, flush hoses., replace drier. Remember there will not be any oil in the system at this point except compressor if that was re-used. Going this far recommend replacing the hoses and of course add correct AC oil spread throughout system.

Okay, you need to flush every part clean as @fast 99 stated. The compressor oil makes the inside of all the parts sticky. That in turn holds all the shredded compressor guts. Disconnect and flush each part with a solvent based cleaner. I know they sell spray cans with adapters to flush out trans coolers. The hoses may not like any solvent cleaners. That is why you may want to replace them also as stated.

I could go and on and on about aftermarket and (rebuilt) parts.... I'll shut up...
It's OK to flush them in place? All the solvent will come out?
 

75gmck25

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Use A/C flush, not any other solvent, and it should be fine. It is designed to flush out the liquid completely, and any remaining residue is compatible with common A/C refrigerants and oils.

Old design condensers have fairly large passages, but later on they switched to a more effective design (piccolo, etc.) that has quite small passages. Not sure when they made the changes to squarebody trucks.

If you have pulled the orifice valve assembly, evaporator should be easy to flush cleanly. Receiver/drier will need to be replaced. One hose may have a muffler (looks like a tin can). Not sure how well it flushes.
 

louu

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Use A/C flush, not any other solvent, and it should be fine. It is designed to flush out the liquid completely, and any remaining residue is compatible with common A/C refrigerants and oils.

Old design condensers have fairly large passages, but later on they switched to a more effective design (piccolo, etc.) that has quite small passages. Not sure when they made the changes to squarebody trucks.

If you have pulled the orifice valve assembly, evaporator should be easy to flush cleanly. Receiver/drier will need to be replaced. One hose may have a muffler (looks like a tin can). Not sure how well it flushes.
Awesome, I'm gona do it. Might be a couple of weeks though I got a lot going on right now.

Really appreciate all the help guys. I'll report back when I'm done
 

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