Hi. My 2000 Ranger (purchased last summer) has no A/C. I located a large hole in the ac line that I was able to successfully patch. So I charged the system. The A/C clutch would not engage so I bypassed the relay to start it hoping it would help get refrigerant into the system. Well I am not sure what the problem is. But when I charged it I heard a hissing sound in the (toward the cab) back side of the A/C compressor. I could not locate a hole. I used refrigerant with dye and could not see any where I heard the noise. I added more and still nothing but the hiss. And inside the truck it does not get colder. Any tips or insight? Or do I have to take it to a shop?

 

You need to test the pressure in the system so rent an AC gauge set or take it to a shop

AC systems have two pressure switches that will prevent compressor from starting
A low pressure switch so compressor won't start without any OIL circulating, AC "freon" has oil in it that lubes compressor while its running
High pressure switch so AC lines won't BLOW OFF if system gets clogged

Also, if system had a hole and had no pressure for over a month or so then the receiver/drier needs to be replaced or system WILL clogged up
AC system needs to be purged of moisture or it can't work
Thats what the Drier does, it absorbs moisture, if drier is exposed to air, a hole in the system, then it absorbs that moisture so its DONE, can't absorb any more
If there is any moisture in the system it will FREEZE in the pipes blocking flow
Receiver/drier is not expensive
There is also a filter that needs to be changed

 

Ok. Yes it had a hole for longer than that. Before I owned it. Ok so maybe I can replace that part and try again. Thanks. I will rent a gauge if I have to. But the clutch definitely doesn't engage. I swapped relay with horn and still no. Hole was down near bottom of radiator. Something had rubbed on it and it was good size hole.

 

I would get the gauges FIRST, test that the system can HOLD pressure, otherwise you will be wasting money on "freon"

There are many many videos and how-tos on using these gauges correctly

 

So in addition to the drier I also need to replace a filter? Can I replace drier and then check AC pressure?

 

Yes, Filter is also called Orifice tube, drier should come with a new one

When you pull out the old one if you see metal bits then compressor is bad/failing