A/C clutch smokes after recharging

[ZiggyPA]

I've had the A/C recharged and when the climate control was activated, the A/C clutch began to smoke.
The A/C guy told me it was probably rusty and needed to be replaced.
He advised against using any oil to lubricate it since that would be conductive.
Is it hard to replace the clutch? Can it be done without removing the compressor?

[Scrapper]

Originally Posted by ZiggyPA

I've had the A/C recharged and when the climate control was activated, the A/C clutch began to smoke.
The A/C guy told me it was probably rusty and needed to be replaced.
He advised against using any oil to lubricate it since that would be conductive.
Is it hard to replace the clutch? Can it be done without removing the compressor?

if you got room you can put ac cluth with out removing it. did it come out of it when you ran it awhile?

[ZiggyPA]

I don't know how much room you need. It looks pretty tight.
I am now trying to put WD40 in it, engage the clutch for a couple of seconds and more WD40. There is not much too loose...

[HotZ28]

What are the high/low side pressures? You could have a clogged expansion valve (screen) creating low high side line pressure and placing a real burden on the clutch. BTW, WD40 is not the solution, it will do more harm than good. Remember, this is a coil activated CLUTCH.

[ZiggyPA]

I'll check with the A/C guy what the pressures were. Is there another name for this expansion valve? I don't see it in the Rockauto catalog.
Just before I had the car idle for a minute with the clutch engaged and it rotated at normal speed and the vents blew cool air.
What damage could the WD40 do? Should I clean it with brake cleaner?

To be precise, the smoke was coming from the gap between clutch and pulley.

[HotZ28]

Expansion valve is the same as an orifice tube. (Shown below)



The clutch hub/assy consist of a clutch, clutch coil, pulley & bearing. Individual parts to replace the clutch hub assy would cost more than a new compressor with clutch assy. WD40 acts as a lubricant and when comes in contact with the friction disc it can (will) cause slipping. Clean with brake clean! Have you removed the drive belt to check the clutch gap and the condition of bearing?

[ZiggyPA]

I did check the clutch gap, it was over 1 mm (.040). I yet have to replace the belt (and idler pulley as you advised)
To see what is going on, I had the car idle while monitoring the temperature of the clutch/pulley.
When it is not engaged, it is about 165 degrees (other pulleys are ±150 except for the alternator which is also ±165)
When the clutch engages it seems to cool and cycle normally (ambient temperature ±70)
After 5 or 10 minutes, the clutch began slipping and the temperature began to rise. At about 230 it began to smoke and I turned the A/C off.
After having it cool to 165, I repeated the test. After a couple of minutes, the clutch began slipping again and I turned the A/C off when it had risen to 195 degrees.
Would this be a bad coil? The clutch didn't turn any heavier at that point than before. Testing was before using brake cleaner btw...
I'm interested to hear what you make of this.

[HotZ28]

The air gap between frictional surfaces of the clutch plate and clutch rotor, should be 0.50-0.76 mm (.020-.030). It sounds like your gap is too wide, the magnetic clutch coil is getting weak, or the bearing is binding. As previously mentioned, before condemning all compressor/clutch parts, you need to have the pressures monitored, especially when the clutch begins to slip. A blocked orifice valve will cause the same symptoms.

[ZiggyPA]

Ok thanks I will have the pressures checked. At Rockauto they have 9 different orifice tubes, ranging from 0,62 ct to $35 and they all seem the same to me! Which one would I need?

[HotZ28]

Four Seasons Part # 623, or ACDELCO Part # 155754 will work fine.

[ZiggyPA]

Thanks! So if I understand this right, if the orifice tube is clogged, the a/c compressor will turn so heavily that it causes the clutch to slip?

I read somewhere that the resistance of the coil can be measured on the socket, is it useful to do this?

[HotZ28]

Originally Posted by ZiggyPA

Thanks! So if I understand this right, if the orifice tube is clogged, the a/c compressor will turn so heavily that it causes the clutch to slip?

If the orifice tube is clogged, high side pressure will be low placing a burden on the clutch. Typically, (depending on ambient) the high side pressure should range between 200-250 psig. If too low, or to high (above 300 psig), you have a problem.

I read somewhere that the resistance of the coil can be measured on the socket, is it useful to do this?

I don't know what purpose this would serve in this case. You said the clutch will engage when the system is first turned on; so therefore, it sounds like the coil is not the problem.

[ZiggyPA]

That makes sense. At Autozone they mention replacing the O ring too. Which O ring would be the right?

http://www.rockauto.com/catalog/x,ca...,parttype,6944

[HotZ28]

IIRC, it would be the 9mm O-ring. Rather than take a chance, just get an A/C O-ring assortment at your local parts store. Was the system converted to 134a in the past? If the orifice screen is blocked, you have a bigger problem. I would wait & see what you find with the pressure test, before proceeding with other repairs.

[ZiggyPA]

No, it has not been converted to r134a. What if the orifice screen is blocked? Wouldn't it suffice to replace it?