A/C only blowing 60 degrees from vents. (3 Viewers)

[Danford1]

Hi, I know this is a Toyota forum and I have an old Ford. The A/C systems should be the same.
I have an old 67 Falcon. It is a factory A/C can. I installed all new under hood components from Classic Auto Air and used the recommended 24 ounces R134A. All was Great for many years. Duct temps were is the 30’s not anymore. It blows 60 degrees now after recent evacuation, vacuum and recharge with 2 cans r134a.
Pressures are 35-40 and 160-170.
The low side line is very cold, the expansion valve is very cold too. The compressor itself is cold and almost frosty, drips condensation. The heater core isn't hooked up so that isn't adding heat to the system.
I have the old expansion valve with the copper tube running to a bulb. I tried clamping bulb to cold side of evaporator line and also just let the bulb hang in the hot under hood air. No change in duct temp. Do I need a new expansion valve? What else can I check? 60 degree air isn't cold enough. It used to blow in the 30's.
Thanks

 

[aztoyman]

It sounds like it's cooling "something" well. Just not your air. Is the evaporator plugged externally? Gotta get air through it to cool it.

We've had a bunch of 66-67 Mustangs and they all had the under dash A/C so I'm not familiar with duct work in the early cars. If the evaporator isn't plugged, I guess make sure the air going across it is actually going through the ducts and not lost to leaks or obstructions.

What made you service it in the first place?

Scott in AZ.

 

[aztoyman]

I see you're in Michigan. The humidity is crazy there so it's possible the evaporator froze up too. I had a Suburban that I could run super cold here in AZ. When I traveled back to Buffalo my evaporator would turn into a block of ice. I had to adjust the low pressure switch to kick the compressor off sooner when I was in high humidity. Just another idea.