AC compressor makes strange noise....do I need to replace?

When I turn my AC or defroster on the compressor now cycles on and off every 5 seconds and the electric fan never kicks on. I am guessing that it is low on Refrigerant...but thats not my main concern:

When it engages, the compressor is making a loud single "CLACK" each time. I did a seach on AC noises but no one seems to describe this CLACK. I am wondering if thats a sign that the bearings or clutch is on its way out? I am guessing so, but want to make sure before spending the $ on a new compressor.

it's normal for it to "click" when the clutch engages, but a "louder than usual" noise or an audible looseness that sounds like a clack would indicate poor clutch engagement. Causes for this are usually narrowed down to failing clutch, improper gap between the clutch plates, or insufficient power supply to the clutch coil. Verify +12V to the coil, sound ground circuit, and proper gap (no clue of the correct gap on these) and you'll have narrowed it down to the clutch.............. maybe......

Might be normal. You can take the plug off the accumulator/filter at the pressure switch, jump acrsoss the plug, and see how the compressor kicks in and runs. You need to do that to recharge anyway. But don't leave it that way very long (like not hours). Listen for noisy compressor running or excessive resistance that would indicate compressor failure.

winterbeater said:

Might be normal. You can take the plug off the accumulator/filter at the pressure switch, jump acrsoss the plug, and see how the compressor kicks in and runs. You need to do that to recharge anyway. But don't leave it that way very long (like not hours). Listen for noisy compressor running or excessive resistance that would indicate compressor failure.

Click to expand...

Winterbeater - Could you describe in a bit more detail how to "jump across the plug"? I dont have much experience with AC systems. Thanks.

Take a short piece of wire (3" or so) with the ends cleared (1/2" or so) of insulation and stick one end in one side of the plug that you unplugged from the accumulator bottle and stick the other end in the other side of the plug. This will do what the pressure switch does when it senses enough refridgerant pressure in the system for it to run properly. It is hard to even get the system to take refridgerant in when recharging without jumping this switch.

Pretty simple....I will give it a try. Thanks again.