How to fix A/C

[vrinner]

A/C doesn't blow cold but I do hear it clicking on and off. I'm guessing it's just low on R12. Went to AutoZone and no R12. Can this stuff still be had?

Also what does it take to convert to R132 (or whatever the new stuff is called)?

Thanks!

[WillyB93]

Sounds like it is just a little low or the orifice filter is clogged. Some people still have a few cans of R-12 here and there, kinda depends where you are. R-134 is the new stuff all it takes is a different fitting then R-12 to use it.

[jstanley55]

Have it leak checked. R12 doesn't just evaporate. If you're low you have a leak.

[Z282SLO]

R12 (freon) has not been available for quite some time. Conversion to R134 at a Ford dealer is not very expensive (less than $200).

[buddha]

Agreed, I would just do the conversion...........after you find the leak.

Sometimes the leaks are pretty obvious. The system has oil in the system, so just look for connections on the system that are all oily.

[vrinner]

So I've seen some other posts that just say purge out the old R12 and then refile with R134 (after fixing any leaks).

Is it that easy? How do you purge the old R12.

[Z282SLO]

So I've seen some other posts that just say purge out the old R12 and then refile with R134 (after fixing any leaks).

Is it that easy? How do you purge the old R12.

Those posts are wrong. R12 systems are not compatible w/R134 systems.

[vrinner]

So I've seen some other posts that just say purge out the old R12 and then refile with R134 (after fixing any leaks).

Is it that easy? How do you purge the old R12.

Those posts are wrong. R12 systems are not compatible w/R134 systems.

So what is the proper procedure? What does the dealer do and is this something that a home mechanic can do?

[WillyB93]

They have a machine that sucks the old freon out into a extra reservoir, then the pressure check the system. Some may change the orifice filter in the process, if the pressure is holding stead then they start re-charging the system adding PAG oil, and the recommended amount of freon (which should be on the tag on the radiator support). The amount has to be correct, if too much you can lock the compressor up or not enough it will not engage the compressor. Everyone has there own ways of doing things, but you really aren't supposed to just dump the old into the open air.

[buddha]

If the compressor isn't engaging, then any R12 left in the system is minimal.............it's already leaked into the atmosphere.


Complete upgrade using new stuff:

http://www.latemodelrestoration.com/ite ... -To-R-134A


You can reuse your existing parts, but it requires all new seals, dryer, and removing the R12 oil and any coolant.

[1993cobra]

Check for any obvious leaks, oily connections. It took it 20 years to leak to this point. If it has just gotten to the point the compressor won't come on, 1 can would probably get you going. Check ebay or craigslist for a can of r12.i stashed 2 box ex back around 1990. Also check your low pressure cycle switch they do go bad. Its the switch that screws onto the dryer.

[vrinner]

Check for any obvious leaks, oily connections. It took it 20 years to leak to this point. If it has just gotten to the point the compressor won't come on, 1 can would probably get you going. Check ebay or craigslist for a can of r12.i stashed 2 box ex back around 1990. Also check your low pressure cycle switch they do go bad. Its the switch that screws onto the dryer.

Yeah...I think going on Cragslist and getting some r12 would be the easiest bet. Need to go find the leak first though. I'm guessing that if I have to replace any seals that any R12 left in the system will go to atmosphere?

[Cobra Jet]

Before you go spending big $ on the A/C diagnosis, freon purge/refill or parts hunting - check the A/C Pressure Switch at the firewall on top of the accumulator (black cylindrical part on firewall, passenger side).

Pull the harness off the switch. Jumper that connector on the harness using a paper clip by bridging both contacts. Place the harness connector onto a cotton towel. Once jumpered (and paper clip is secure and not near anything else metal), start the car and turn the A/C to "on". If the system does still have freon the A/C compressor should kick on and cold air should start pumping (system should operate normally). If that happens, the pressure switch was faulty - very, very common failure part on the 85-95 5.0's.

The part itself is about $10-$15 (or less) depending on where you buy it. To replace, just grasp the switch and spin it counterclockwise to remove it from the top of the accumulator. It may make a slight *pop* sound once it comes off - this is normal. Install the new one in the same manner, just hand tighten it, DO NOT overtighten it. Plug connector back onto switch.

The 5.0 A/C compressors are also known to leak or seep freon out of the front seal. Based on what I remember, the seal can be replaced - but IIRC, it may require purging the remaining freon. Take your hand and with the engine off, feel under and around the front of the compressor - if you end up with oily residue on your hand or a towel, front seal is bad.

Hope something above is helpful - check the pressure switch first - least expensive and easiest part to fix.

[1986Browns]

Before you go spending big $ on the A/C diagnosis, freon purge/refill or parts hunting - check the A/C Pressure Switch at the firewall on top of the accumulator (black cylindrical part on firewall, passenger side).

Pull the harness off the switch. Jumper that connector on the harness using a paper clip by bridging both contacts. Place the harness connector onto a cotton towel. Once jumpered (and paper clip is secure and not near anything else metal), start the car and turn the A/C to "on". If the system does still have freon the A/C compressor should kick on and cold air should start pumping (system should operate normally). If that happens, the pressure switch was faulty - very, very common failure part on the 85-95 5.0's.

The part itself is about $10-$15 (or less) depending on where you buy it. To replace, just grasp the switch and spin it counterclockwise to remove it from the top of the accumulator. It may make a slight *pop* sound once it comes off - this is normal. Install the new one in the same manner, just hand tighten it, DO NOT overtighten it. Plug connector back onto switch.

The 5.0 A/C compressors are also known to leak or seep freon out of the front seal. Based on what I remember, the seal can be replaced - but IIRC, it may require purging the remaining freon. Take your hand and with the engine off, feel under and around the front of the compressor - if you end up with oily residue on your hand or a towel, front seal is bad.

Hope something above is helpful - check the pressure switch first - least expensive and easiest part to fix.

EXCELLENT tech advice right here!!!! You Sir need to post more often!

[Z282SLO]

This is one of several excellent posts from Cobra Jet recently. Hey Admin, I think he deserves a complimentary registry T-shirt.

Maybe if he has a registry T-shirt, he'll sell his '94 and get the one and only '93 Cobra!