1963 AC evaporator core leaking?

[Mark Geertsma]

Hi all,

Again I have issues with my AC system. Had it refilled recently but within a few days the system was empty again. The AC mechanic added tracer fluid to check for leaks, but there are no visible leaks anywhere. I’m starting to think it’s the evaporator core as this is the only place that can’t be checked.

From your experience, how likely is it that the evaporator core is leaking?

And how easy (or not) is it to replace the core?

[Kurt]

It's possible that the evaporator core is leaking. There are electronic freon detectors that "sniff" the air and  beep when they detect freon (& other gasses). These are good for finding leaks from inside the A/C box through the vents. Of course if the system is empty, you'd have to put some refrigerant in1st. Worst case, the evaporator can be accessed if you take the right front wheel off. If I remember correctly, there is a panel in the wheel housing to remove for access to the evaporator core. If you still have the STV (suction throttling valve) on your system, the diaphragm tends to leak. I replaced mine a few times over the years and finally eliminated it with a modification kit. So far, so good.