AC Compressor occasional noise.

[Seosamh]

Hello all.
My 1990 K1500 AC works like it always has blowing cold air. However today it made a loud noise that sounded like a miniature air compressor along with an unusual but definitely not a burning smell. It almost seems to me like its over charged though it's never been serviced since I bought it in 2012. Before I purchase a new compressor, receiver dryer and orifice filter I was hoping someone may have seen this over the years. Tonight when it gets dark I plan to try and recreate what it's doing while shining a UV light at it. Also the clutch works quietly and there is no belt slippage/squeal. Any advice would be greatly appreciated. Thanks.

 

[GoToGuy]

Do have dye installed? Have you checked your pressures against the charted numbers for temp and humidity and what conditioned air should be? Some 134 may have migrated out. Which could cause different compressor noise if cycling faster. Is it happening constantly. Or just a single hiccup.

 

[Seosamh]

Thanks! I was hopeful on this just like your reply, till I took this photo. Scroll down. I like the challenge in this and each symptom in order as found. The best symptom was the compressor too hot to touch after a 90 sec run. My wife said buy a 2024 Silverado, I said no since I Wouldn't have anything to work on.

You must be registered for see images attach

 

[Schurkey]

If you're smelling something, I'd be looking at the HVAC fan instead of the compressor.

Unless the smell from the compressor is leaking out of the engine compartment and then getting sucked into the plenum at the base of the windshield, I don't know how you'd smell anything within the refrigerant system.

 

[Erik the Awful]

However today it made a loud noise that sounded like a miniature air compressor along with an unusual but definitely not a burning smell.

f you're smelling something, I'd be looking at the HVAC fan instead of the compressor.

Drop the blower motor out and inspect it before you go any further.