AC Problem

[Grav]

Hi Guys,

First post here so I hope you Auto junkies can shed some light on my problem.

AC refrigerant was low to none. I filled with 134a and the compressor started kicking in but marginal cold air. When I shut off the engine I could hear a hissing under the hood.

I checked tubes and hoses but couldn't find a leak. I turned the clutch plate on the compressor by hand about a half inch and the hissing stopped. When moving it back to original position the hiss started again until it emptied.

Is the compressor bad or am I missing something else.

Thanks in advance for the help.

[Crvett69]

sounds like your compressor is leaking but best way to tell is to get the r134a that has the dye in it. then you can use a flashlight or blacklight to look for where the dye is coming out

[tomj76]

I agree with Crvett69. You most likely have a bad seal in the compressor. The die will show up between the pully and the front of the compressor body if you have a leak.

To repair the seal you must remove the compressor and replace the dryer/accumulator. After that you'll need to pump down the whole system with a good vacuum pump to purge the system of air and water. It helps to have a good HVAC manifold to do the pump down and recharge of the system.

I personally have done these things, but only b/c I had access to the tools and know how. This is may not be a DIY repair unless you're equipped for and skilled in HVAC repair.

[Grav]

Thanks guys. I did put the dye in and used a black light to look for the leak. I checked all the hoses and tubing I could see as well a a good check around the compressor and nothing. Very strange as I can hear the leak as clear as day when the system is charged. Honestly there is so much frame rust on the thing that I guess its time to say bye bye anyway. Thanks so much for your help.

[tomj76]

If you have THAT bad of a leak, I'd use another gas instead of refrigerant, or I"d use it sparingly. If you have rear A/C then there are pipes running under the vehicle that could be rusted.

Also, be sure you're not mistaking the sound of refrigerant running through the orifice tube (located on the passenger side of the vehicle on the firewall behind the engine. It hisses too when the A/C shuts down as the high pressure equalizes with the low pressure.