I have a 2003 Lincoln Navigator. We have had a clicking sound that somes and goes. Today I think I narrowed it down to the AC compressor. Is this a common problem? Any recommendations on what needs to be done? Thanks for any advice.

 

Your compressor has a clutch that clicks when it engages.
If your a/c is working properly, you shouldn't have it cycle often enough to notice.
However, if you are low on freon, there's a low pressure switch to protect the compressor from operating in a low condition and can cause it to cycle on and off frequently.
I would check your freon level first before anything else.

Also, If it wont stay on, the clutch shims can wear to the point where the circuit won't allow the clutch to stay closed/on.

They are known to wear out after time and use.

 

I'd check first to see if your AC works well or not instead of checking refrigerant levels. If it does, I'd simply get used to the clicking or, if you can't, just put a new clutch plate on it.

 

My AC does not work well. The clicking comes and goes. When it is clicking it is a steady clicking like the fan is hitting something.

 

I've dealt with clicking noises that turned out to be a bad bearing. Is the belt tensioner pulley steady as the engine is running or does it jump whenever the clicking happens?

 

I haven't noticed any difference in the pully's when it's clicking. It's a steady click that I 1st thought was a lifter but I couldn't hear anything coming from the valve cover. I listened with long screw driver and finally narrowed it down to the compressor.

 

When it is clicking turn off the climate control and see if it stops. If it continues, and the A/C clutch is disengaged, it could be a bad pulley bearing. If it only clicks when the A/C clutch is engaged it could be the compressor is heading toward death.

 

I go back to original point, check the freon level, especially if it's not cooling properly.
It won't cool properly because the compressor isn't working properly due to either the freon or clutch assembly.
Alloro makes a good point with the bearing but if it was going bad, you would still have good a/c for a while.
Get can of R-134 with a gauge for the simple test. You can only fill one way as both high and low sides are different sizes and can't be improperly attached.

 

Yes of course, the first thing to make sure of is that the A/C clutch is not cycling on and off.

 

Will the AC clutch cycle that quick(sounding like the engine has a knock) if I'm out of freon with the AC turned off? I've obviously never played with these before. Thanks for the help.

 

Nope, that's why I suggested a bearing. But to be prudent you do first have to confirm that the clutch is not the source of the noise due to a rapid on/off cycling.

 

I bought a can of R-134 with the gauge. I will be putting that in tomorrow. I'll let you know how that goes.

 

I hooked up the gauge and it reads a steady 65psi. It doesn't cycle at all. I hooked the gauge up to my Taurus and it cycled properly so I know the gauge is working. The gauge says 65psi is between overcharged and mechanical problem. Any idea what's going on?

 

The compressor isn't running. A simple visual check of the clutch hub would have told you the same thing.

Take the serpentine belt off, take off the hub (inspect it), and check the pulley bearing by hand.

 

I took off the serpentine belt. The pully doesn't spin smoothly. It has a tight spot approximately every revolution. I compared this to my other truck. The pully on my truck spins smooth. I assume this is the source of my problem. What should I be doing now? Thanks.