Q: The clutch on my ac compresser is leaking out really thick black tar like stuff when it is spinning. What is it? And why is it doi

asked by on August 22, 2017

My clutch to to the ac compresser is spitting out really thick black tar like stuff out when it engages and spins. What is it? And why? I checked the the charge on the low port and it had way to much pressure in it.

My car has 200000 miles.
My car has an automatic transmission.

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Hello, thank you for writing in. A black goo coming from the air conditioning compressor is more commonly known as "black death". It occurs when the refrigerant in the air system breaks down and is no longer the chemical it was when it was put into the system. It can happen with old refrigerant or poor quality refrigerant that is not properly maintained. "Black death" can also occur when the compressor starts to wear down, and it can be amplified by bits of metal from the compressor getting into the refrigerant. It can cause a lot of issues with the system if it is allowed to continue on. You can attempt to flush the system and recharge it, but the black goo does cause issues with the components it contaminates. Expect there to be other issues, and consider yourself lucky if there is no further damage beyond the compressor. For help flushing and inspecting the AC system, contact our service department to schedule an appointment.

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