>While trying to get my 318 A/C working I found that the low pressure switch
>is in the open position causing the compressor clutch to stay disengaged.
>Q.: Could it be low on refrigerant or is the switch defective ?

The only way to tell (safely) is to put gauges on the freon system
and jumper the switch (briefly!). If you get normal pressures, your
switch is faulty.

I don't recommend bypassing the switch without gauges; if there is no
freon in the system, and it is low on oil, it could harm the
compressor.

Take it to an AC professional if you don't have access to gauges.

Dave

--
Dave Carpenter

Whatever you wish for me,
May you have twice as much.