I think I have a good idea of what needs to be done. But, I need a little more confirmation prior to moving ahead.

My A/C is not blowing cold. The A/C compressor clutch is not engaging. It attempts to do so every five seconds or so.

Does the A/C compressor clutch need to be replaced?
Should the entire A/C compressor assembly be replaced?

Also, the A/C compressor is easily accessible. I've never changed out one of these before. My experience has been with replacing starters, alternators, belts, motor mounts, etc... Is this something I can do on my own or should I have it done by a mechanic?

 

Have you confirmed the compressor isn't engaging? The compressor is easy to replace once the system is depressurized. However, just because the air isn't cold doesn't mean the compressor is bad.

 

The compressor clutch is cycling because your system is low on R134A. This means you have a leak somewhere. Look around the A/c Lines for crud buildup as this would indicate a leak. You can also buy some refridgerant dye and put it in there and get a black light and look for the leak yourself. Our compressor was so bad that it made the liner on the hood all wet and nasty. I installed a junkyard compressor for 50 bucks. On our 94 ranger it was 4 bolts, and 1 bolt that hooked the lines into the back of the compressor. Also a wiring harness needs to be unplugged. I repleaced ours when i was like 16, so i think anyone could probably handle it. Then just go to a parts store and buy some R134A and recharge it.

If you want go ahead and fill the system first, and put in some dye. What you do is start the truck, turn the a/c and defrost on, and turn it to pure cold, Then when you buy a can you can get one with a nozzle on it, or you can get a serpeate nozzle that cans will screw onto, either is fine. In the engine compartment near the heater core there is a steel can that looks like it would hold tennis *****, there is a line coming off of that with a cap on it. This is the low pressure side, simply pull the cap off and there should be something similar to a quick disconnect like on an impact gun or air hose. Simply hook your can up to that, shake it, turn it upside down with the truck running, be carefull to keep an eye on the gauge though, you dont want to overpressurize the system. If everything is right with the compressor and the clutch after filling the system it should start to cycle on and off less, until it does it at its normal rate.

Oh, and welcome to FTE!

 

That was it!!! Cold as ever!!! Thanks for everything!!!

 

Remember you still have a refrigerant leak, most likely at an O ring in a line connection, so it will fail again, when? that depends on how bad and where the leak is located. You should be adding R-134A with oil in it, not pure R134A, as when it leaks out, oil leaks out with it, and if you don't replace the oil, sooner or later the compressor will eventually fail.
You can also find the leak with a bottle of Mr Bubble or soap and water, just put it on the fittings when the engine and system are turned off, and look for bubbles.
If you cant find any leaks, and the clutch is oily and dirty, the leak could be in the compressors seal, and the compressor would need to be replaced to stop the leak.
Repairing the leak first is a much more permanent repair.