Jim Grant's Tech Tips
Ford Ranger, A/C Conversion
Q: I recently converted my '86 Ford Ranger's
A/C system to R-134a. I changed the compressor, accumulator, orifice tube,
and compressor cycling switch. The system works fine at idle speed but
the compressor cycles at three second intervals at highway speed. I know
that this type of system is supposed to cycle, but is this the normal
rate? What can I do to fix it if it is not?
A/C system in your vehicle is not supposed to cycle at that rate and the
conversion to R-134a refrigerant is not the cause of the problem. If all
the electrical components are in good condition, a rapidly cycling A/C
system is an indication of a low charge of refrigerant or a restriction
in the system. The A/C system operating pressures have to be monitored
while driving the vehicle. With the right information you'll be able to
identify what repairs are needed.