Ac Lines
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The condenser is up front of the radiator. It has a hot gas line the comes off the compressor and a hot liquid line that comes off the condenser and connects to the firewall and evaporator.
Since you are not familiar with how A/C works, here some background theory:
The condenser is up front of the radiator, and it is supposed to condense the hot gas from the compressor into a hot liquid. The hot liquid goes to the expansion valve located in the tubing next to the firewall. The expansion valve lets the hot liquid expand and become a cold gas, the cold gas goes to the evaporator inside the car where the fan blows on the evaporator exterior. The heat transfer from the air inside the car to the cold gas inside the evaporator causes the A/C to blow cold air. The now cool gas goes to the compressor where it gets compressed again into a hot gas and the process starts all over again. Keep in mind that this is a closed system, and the gas inside the A/C doesn't get out unless there is a leak.
Here's where the problem gets sticky. All the original fox body 79-93 Mustangs were made to use R12 refrigerant. R12 is no longer available unless you have an EPA 609 license or ignore the law and buy it off eBay. That means the system needs to be converted to use R134. Putting R134 on top of R12 without doing a proper conversion will cause compressor failure and metal from the compressor will circulate throughout the system. When this happens, it requires an extensive and expensive flush of the A/C system to get all the metal and other contaminants out. Skip doing the flush and clean thing and the new compressor will quickly fail.
When a R134 conversion is done, the installer is supposed to replace the service fittings with R134 style quick connector couplings.
the R134a service fittings on the system: the red goes on the high side and the blue on the low side. This will help others identify that a R134a conversion has been done on the system.
Typical low pressure side R134 coupling
Typical high pressure side R134 coupling
R134 only
Then put the R134a Service Sticker on, secure all the loose wiring on the system and you are done.
The typical sticker looks like this, yours may be different.
They are also supposed to replace all the O rings with R134 compatible O rings. The R134 gas molecule is smaller than the R12 molecule, so R12 O rings will be prone to leakage.
See http://bellsouthpwp.net/l/r/lrichker/Mustang_tech/R134a_conversion/r134a_conversion.htm for R134a Conversion & recharge help
If the gas leaks out, usually it is because one of the O ring seals is bad. High quality R134 conversion is supposed to include new green O rings for all the joints and couplings. When you open the system to replace the O rings, all of the refrigerant must be removed and recovered and the system vacuumed down prior to recharging.
R134 recharge kits with refrigerant/leak detector dye can are available at most auto parts stores. Some of the R134 refrigerant refills have a leak stop in them. BUT beware! The stop leak can block the expansion valve, causing system failure. The refrigerant/dye recharge kits are popular because the green dye makes a very visible indicator where the leaks is. Some of the recharge kits include a pressure gauge so you have some idea of how much refrigerant is in the system while it is running.
The compressor/motor is also known as the hermetic unit, because it is hermetically sealed. It looks like a oversized paint can with tubes and wires coming out of it, and it is located in the bottom of most refrigerators. One tube is the pressure side and the other tube is the suction side. There may be a capacitor to help it start or run, usually the wiring diagram is stuck somewhere near the unit.
Since you are not familiar with how A/C works, here some background theory:
The condenser is up front of the radiator, and it is supposed to condense the hot gas from the compressor into a hot liquid. The hot liquid goes to the expansion valve located in the tubing next to the firewall. The expansion valve lets the hot liquid expand and become a cold gas, the cold gas goes to the evaporator inside the car where the fan blows on the evaporator exterior. The heat transfer from the air inside the car to the cold gas inside the evaporator causes the A/C to blow cold air. The now cool gas goes to the compressor where it gets compressed again into a hot gas and the process starts all over again. Keep in mind that this is a closed system, and the gas inside the A/C doesn't get out unless there is a leak.
Here's where the problem gets sticky. All the original fox body 79-93 Mustangs were made to use R12 refrigerant. R12 is no longer available unless you have an EPA 609 license or ignore the law and buy it off eBay. That means the system needs to be converted to use R134. Putting R134 on top of R12 without doing a proper conversion will cause compressor failure and metal from the compressor will circulate throughout the system. When this happens, it requires an extensive and expensive flush of the A/C system to get all the metal and other contaminants out. Skip doing the flush and clean thing and the new compressor will quickly fail.
When a R134 conversion is done, the installer is supposed to replace the service fittings with R134 style quick connector couplings.
the R134a service fittings on the system: the red goes on the high side and the blue on the low side. This will help others identify that a R134a conversion has been done on the system.
Typical low pressure side R134 coupling
Typical high pressure side R134 coupling
R134 only
Then put the R134a Service Sticker on, secure all the loose wiring on the system and you are done.
The typical sticker looks like this, yours may be different.
They are also supposed to replace all the O rings with R134 compatible O rings. The R134 gas molecule is smaller than the R12 molecule, so R12 O rings will be prone to leakage.
See http://bellsouthpwp.net/l/r/lrichker/Mustang_tech/R134a_conversion/r134a_conversion.htm for R134a Conversion & recharge help
If the gas leaks out, usually it is because one of the O ring seals is bad. High quality R134 conversion is supposed to include new green O rings for all the joints and couplings. When you open the system to replace the O rings, all of the refrigerant must be removed and recovered and the system vacuumed down prior to recharging.
R134 recharge kits with refrigerant/leak detector dye can are available at most auto parts stores. Some of the R134 refrigerant refills have a leak stop in them. BUT beware! The stop leak can block the expansion valve, causing system failure. The refrigerant/dye recharge kits are popular because the green dye makes a very visible indicator where the leaks is. Some of the recharge kits include a pressure gauge so you have some idea of how much refrigerant is in the system while it is running.
The compressor/motor is also known as the hermetic unit, because it is hermetically sealed. It looks like a oversized paint can with tubes and wires coming out of it, and it is located in the bottom of most refrigerators. One tube is the pressure side and the other tube is the suction side. There may be a capacitor to help it start or run, usually the wiring diagram is stuck somewhere near the unit.
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Thank you for the info, I follow what your saying. I have a new ac manifold from pump. The other two lines coming off condenser, are they called the discharge line and suction line. Also the office tube? Is that what I buy, can't find a good ac line diagram or picture anywhere.
Davis thank you very much, that does help allot. I can't believe I missed that thread Google for days. That sensor I will probally need to get, guess use zip ties in place of cable clips. I can say I don't think the evaporator is connected to firewall, but it looks like a newer 4 seasons unit. Come next week I will have all the lines, I'll look for that sensor on the net. Thanks for the help.
Ok, so I went to get filled, and couldn't get it to hold vacuum. Me and the mechanic replaced the orings on compressor and it got vacuum but was leaking from compressor at manifold. Here is the deal, I cannot seem to get the manifold to completely seal at compressor, this is a new line with new orings in compressor. Are the suppose to be seals on the manifold? That one bolt doesn't seem to be the best setup, doesn't seem to apply enough pressure to seal both ports. Any ideas
