I'm trying to get my A/C working on the '88 GT in time for winter
and it's time to throw out the lifeline. It's leaking, and I'm trying to find it and fix it.
I had a compressor in it that I replaced in 2002, which worked until about 2010. In 2013 I pulled the engine and interior for a major restoration, which went until 2017.
I replaced the O-rings at the rear manifold lines, the compressor, the accumulator, the LPCO, and the orifice tube. Still leaking under vacuum.
Took it to a shop to have it sniffed. Compressor is leaking they said, I figured probably the shaft seal.
I replaced the compressor, orifice tube & accumulator. NEW 4-seasons compressor, NOT reman.
At this point it held full 1" vacuum overnight.
Tried charging it. All seemed to be going well. At about 65F ambient, both sides got to about 50psi with 2 cans. All passive slow charge, engine & compressor NOT running. I screwed the caps on the ports and let it sit overnight as it was too cold to test.
Checked it today, 70F ambient, and the high side is holding at 50psi and the low side is now at 0.
0!There's leak detector in the system. No signs of a leak at the compressor or manifold connection in back, nor up front at the accumulator or high side port.
The shop mechanic said he sniffed the condenser and evaporator and they did not appear to showing signs of a leak at that time.
I can't figure out why the low side would leak and the high side would hold, nor why any of this would happen when it holds full vacuum. Anyone?