I reconnected my 1964 Fords ac system. I replaced the condenser and
receiver
dryer with generic ones and hooked it all back up. Still has the York
AC compressor. It held vacuum for 2 days. When I went to put freon in
it and could only get a little more then one can in. The high side
plumbing  gets
hot and there is some cooling in the car but not a lot. You can see
freon running
past the sight glass. The pressure gauges only show a 10 psi
difference between the high side pressure and low side pressure. The
pressures run around 80 on the low side and 90 on the high side,
varying up and down depending on engine speed but always about 10 psi
apart. To try and test the compressor I used the valves on the
compressor to close the hose end and just leave the port connected for
pressure readings. When I close the high side it will run the pressure
up past 300 psi. But when I close the low side it only pulls it down
to 55 psi.

Any thoughts on what the problem is? I'm thinking its either bad
expansion valve or bad compressor. Most new systems have
no trouble pulling the low side down to 25 psi or less but I don't
know what these yorks are supposed to be able to do.