kenfyoozed
Member
I think I am going to pull my engine, and this is an AC car. What is the proper way to disconnect all the hoses / equipment? I am not even sure any of it works.
AC Disconnect / Removal
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LeBaron1973
Old Man with a Hat
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First step is to discover if there is any gas in it and if so, have an air conditioning shop remove it, don't vent into the atmosphere.
I am assuming that you engine probably does not run or you would have started the car to test the A/C. If this vehicle has an RV2 style compressor, it came from the factory with R-12 as a refrigerant. A lot of these systems have been converted to run on R-134a. This conversion usually results in the compressor failing after a year or two. You can test the compressor by placing a socket on the bolt that holds the clutch assembly in place. If you can turn this bolt and rotate the compressor crankshaft two full turns, the compressor is likely still intact. Next, look at the hoses where they attach to the compressor. If there is an acorn cap on the low side and high side service ports, the system was last charged with R-12. If the acorn cap was replaced with a snap type coupling with a plastic slip on cap, the system was converted to R-134a. This is a legal requirement for the R-134a conversion.
If the system was last charged with R-12, the system should be evacuated to remove any R-12 that is still present. If the compressor has seized, it is very likely that there is no refrigerant left in the system as the front seal in the compressor will have failed when the compressor burned out and seized. This would be true for either type of refrigerant.
You should down load a copy of the FSM for your vehicle. The Air Conditioning section gives details on how to disassemble the system. Some of the disassembly instructions are also covered in the Engine Section under Removal. If you plan to reinstall the A/C components, care must be taken when disconnecting the fittings. Many of the A/C fittings are aluminum and the threads tend to seize and this can result in things getting broken. I usually take a propane torch and heat the fittings lightly to help free them up. BEFORE TRYING TO DISCONNECT ANY FITTING BE SURE THAT THE SYSTEM IS FULLY DISCHARGED OR SERIOUS INJURY CAN RESULT. Have somebody who knows what they are doing check the charge first before trying to take anything apart.
Dave
If you are unsure of if the system still has a Freon charge in it, you can remove one of the Shrader valve caps and gently probe the Shrader valve to see if any gas escapes when you depress the valve slightly. IF you get a "hiss", then there's an undetermined amount of gas still in the system.
An observed issue with an a/c shop using a recovery machine to evacuate the system is that using a R-134a recovery machine to recover non-R-134a will result in contamination of the existing R-134a in their machine. The recovery machine takes the oil gas out, cleans it, stores it for re-installation, adding any necessary gas from the machine's cannister of same. Only difference in the R-12 machine and a R-134a machine is the gas in them. So they operate the same, in that respect. End result of using a R-134a machine to remove R-12 is that you might have to pay for a new cannister of R-134a to replace the existing cannister that was contaminated by your suspected R-12. R-134a conversions usually have different service valves screwed onto the existing R-12 service valves AND are color-coded . . . or should be.
Considering that R-12 has been replaced by R-134a since the 1990s, there's no telling what gas is in the system. Could be residual R-12, "something else" of unknown origin, R-134a, etc. Which can lead to the distinct possibility that no a/c shop still had a R-12 recovery machine at this time. Which can bring the "contamination" issue I mentioned into greater focus.
Otherwise, use "line wrenches" on the fittings so you don't end up rounding-off the nuts. You'll also need some a/c-rated O-rings for reassembly, so keep track of what goes where. Plastic bags and a Sharpie work well for that. The securely cap/plug the existing lines so nothing gets inside of them while they are disconnected. You'll also need a new receiver/drier for the system, too.
Just a few things to watch for and be aware of,
CBODY67
An observed issue with an a/c shop using a recovery machine to evacuate the system is that using a R-134a recovery machine to recover non-R-134a will result in contamination of the existing R-134a in their machine. The recovery machine takes the oil gas out, cleans it, stores it for re-installation, adding any necessary gas from the machine's cannister of same. Only difference in the R-12 machine and a R-134a machine is the gas in them. So they operate the same, in that respect. End result of using a R-134a machine to remove R-12 is that you might have to pay for a new cannister of R-134a to replace the existing cannister that was contaminated by your suspected R-12. R-134a conversions usually have different service valves screwed onto the existing R-12 service valves AND are color-coded . . . or should be.
Considering that R-12 has been replaced by R-134a since the 1990s, there's no telling what gas is in the system. Could be residual R-12, "something else" of unknown origin, R-134a, etc. Which can lead to the distinct possibility that no a/c shop still had a R-12 recovery machine at this time. Which can bring the "contamination" issue I mentioned into greater focus.
Otherwise, use "line wrenches" on the fittings so you don't end up rounding-off the nuts. You'll also need some a/c-rated O-rings for reassembly, so keep track of what goes where. Plastic bags and a Sharpie work well for that. The securely cap/plug the existing lines so nothing gets inside of them while they are disconnected. You'll also need a new receiver/drier for the system, too.
Just a few things to watch for and be aware of,
CBODY67
kenfyoozed
Member
here is what i got.....
RV2 compressor, last charged with R-12. High side lines are very rusty indicating extreme care to remove if you are going to try and salvage them. Remove one of the acorn caps, you will see what looks like a tire valve inside. Gently push on the stem to see if any gas vents out. If nothing vents, you can disassemble the system. The fittings on the filter dryer are probably fused to the line, so give them a shot of "break free" or some other penetrating oil before trying to remove them. Same holds true for the rest of the fittings. Evaporator fittings are especially brittle as are the condenser fittings.
Dave
TxDon
Well-Known Member
Interested.
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