A/C Acting Flaky

[alexwolf1216]

So, a few months ago I converted to 134a. My AC system held vacuum, charged up fine and held tight. I had troubles with my mode switch hissing so I rebuilt it when I replaced the radiator and cooling fans, and three days ago BAM no cold air. I saw water coming out of the drain, but the air was cool, at best. It was a little low according to the gauges, so I added another can of 134 2 nights ago. This morning, the AC was super cold, but my compressor was cycling like crazy. It was about every three seconds I heard a click from the relay compartment, and heard the fans coming on and off.

I am guessing I developed a large leak somewhere, but I dont really want to takcle the accumulator/orifice tube based on the horror stories I have read. If I have to, I have to, but it might just be a spring project. I am also pretty sure I will need to do the hoses, but I just had the radiator off.....do I need to remove it again? :angry0:

[Bitsyncmaster]

You can replace the hoses without removing the radiator. Just have to be careful. I had to cut a little of the plastic shroud to get the backup wrench in there.

[David T]

You can replace the hoses without removing the radiator. Just have to be careful. I had to cut a little of the plastic shroud to get the backup wrench in there.

Testing by holding vacuum is not really much of a test. It is a negative 15 psi when you should be doing 150 to 200 psi positive. Sounds like you do have a leak, as you lose refrigerant, just before it gets too low to work, it gets REALLY cold. Cold enough to freeze up the evap coil. Typical leaks are the "O" ring seals, service ports, and hoses.

[alexwolf1216]

Testing by holding vacuum is not really much of a test. It is a negative 15 psi when you should be doing 150 to 200 psi positive. Sounds like you do have a leak, as you lose refrigerant, just before it gets too low to work, it gets REALLY cold. Cold enough to freeze up the evap coil. Typical leaks are the "O" ring seals, service ports, and hoses.

Yea, I replaced the o rings at the compressor, new Scrader valves. I wonder if its worth taking it somewhere to leak test

[DMCMW Dave]

Yea, I replaced the o rings at the compressor, new Scrader valves. I wonder if its worth taking it somewhere to leak test


Depends on your budget for R134 I guess. A large leak is easy to find, smaller leaks generally take some dye, time, and a UV light.

[David T]

Yea, I replaced the o rings at the compressor, new Scrader valves. I wonder if its worth taking it somewhere to leak test

If there is enough refrigerant in the system to get it to run you can try leak-testing yourself. With the system running use soapy water on the high side and when it is not running test the low side. If you see any bubbles you found a leak but keep looking because in all likelihood you have at least several. If the system lost pressure in less than one season you should be able to find most of the big leaks at least.