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Scott V2
September 01, 2010, 16:08
my '02 S-10 which I bought new has started to have bearing failure sounds come from the ac compressor. It has 139k miles on it and runs great beside this new problem. It is the 2.2l engine which apparently is only in 10% of s-10 trucks.

I know it is the AC because the sound starts and stops with me turning the AC on and off. I can make the sound go away or become less by changing the setting from max air to another setting.

I have heard that it could only be an AC clutch going out.

I have also been told that it could be the tension pulley, but the sound seems to be directly coming from the compressor.

I have also read that if it is the clutch, the compressor itself is not too far from going bad as well.

Any method of clearly identifying if it is just the clutch and not the entire compressor?

If it is just the clutch, should I replace the entire thing anyway because the compressor will soon die?

Thanks for any suggestions. I do plan on putting another 80-100k on this one if possible.

flopshot
September 01, 2010, 16:18
seems that if it was the bearing the noise would go away when the clutch was engaged. since the load on the belt changes it would pay to check the idler. i have an 02 S10 and replaced the idler a few months back at 110,000.0 miles. FWIW the engine is the 4.3 V6.

55bird
September 01, 2010, 16:19
Take a long pole wooden and carefully stick it in the suspected area and listen with your ear for the noise.BE CAREFUL!It's a great way to find the source of all kinds of noise.I am assuming you have a good safety between your ears,for this isn't for the amateur to try.

richbug
September 01, 2010, 16:42
The AC clutch has a bearing inside it which acts as an idler when the AC is not engaged. Take the serpentine belt off and wiggle the AC pulley. Is there a good bit of play? The clutch is likely replaceable as a separate part, but on the last one I did, a complete rebuilt pump was cheaper.

Check your other pulleys for play as well while the belt is off.

bob_e95482
September 02, 2010, 05:24
I had a '97 S10, with the 2.2L, I bought it in '01, with 105K on the clock. The air conditioning compressor was shot. Gas gauge didn't work. Valve cover leaked, fouling out plugs. I could go on and on. Except that it ran good, it was the worst POS I've ever owned.

falcom
September 02, 2010, 06:41
If it is the compressor making the noise don't run it. Small pieces of metal get forced through the lines causing the repair to be more expensive.
If it is the belt tensioner it is a $35 part from autozone. If it is the compressor it is $250 part from autozone

JColdIron
September 02, 2010, 10:21
Originally posted by richbug
The AC clutch has a bearing inside it which acts as an idler when the AC is not engaged. Take the serpentine belt off and wiggle the AC pulley. Is there a good bit of play? The clutch is likely replaceable as a separate part, but on the last one I did, a complete rebuilt pump was cheaper.

Check your other pulleys for play as well while the belt is off.

Good advise there. I had the same experience with my jeep. The clutch replacement was more than the new complete unit and required a special puller.

I ended up buying a whole new comp after swapping in a junkyard one that died in less than a year. Those at least had valves on the hoses so that you did not have to pressure down the system to swap. Not so these days.

If you crack the system open make sure to replace everything you can so you do not have to go back sooner rather than later. You need to pull a vacuum to purge the system.

Eric Bryant
September 02, 2010, 22:20
Go to your local parts store of choice, pick up an entire compressor, and do the fix correctly. After 8 years and 140,000 miles, I'm not a big fan of replacing only one component of an assembly that is likely to fail at any moment.

For the record, the AC compressor in my '96 K2500 starting making noise at about 105K, and then sprayed oil all over the engine compartment when the front seal failed a couple thousand miles later. I'd hate to see someone go through the hassle of swapping a clutch, only to have the same compressor failure occur in a few months.

Scott V2
September 04, 2010, 14:08
I just got to taking the belt off and checking everything for wobble. The ONLY pulley that has any play in it is the power steering which is directly below the A/C compressor.

Is it considered normal for the power steering pulley to be able to move forward and back about 1/32"?

The only time I hear the noise is when I run the A/C. Could the load that the A/C pump put on the system make the power steering pump howl? The noise does come from that side of the motor.

richbug
September 04, 2010, 16:19
Originally posted by Scott V2
I just got to taking the belt off and checking everything for wobble. The ONLY pulley that has any play in it is the power steering which is directly below the A/C compressor.

Is it considered normal for the power steering pulley to be able to move forward and back about 1/32"?

The only time I hear the noise is when I run the A/C. Could the load that the A/C pump put on the system make the power steering pump howl? The noise does come from that side of the motor.


I don't have the specs for it, but I suspect 1/32 is fine on that pump.


You sure it isn't a belt noise? How many mile since you changed the belt?

Scott V2
September 04, 2010, 16:40
Originally posted by richbug



I don't have the specs for it, but I suspect 1/32 is fine on that pump.


You sure it isn't a belt noise? How many mile since you changed the belt?

belt has less than 1k on it

richbug
September 05, 2010, 08:58
Originally posted by Scott V2


belt has less than 1k on it

Mind you, I am not a real life mechanic, but an advanced shade tree one. Sounds like you need a compressor.

Scott V2
September 05, 2010, 11:56
Originally posted by richbug


Mind you, I am not a real life mechanic, but an advanced shade tree one. Sounds like you need a compressor.

Sadly I think you are right. I have been doing a lot of research on this and it looks like it. I'm just a bit miffed that I have an uncommon compressor that is going to run me $350-400 instead of $200. The system had a bad condensor and was replaced and fully charged this Spring, I hate having to do this 2x in one year.

Brett
September 05, 2010, 13:57
Since you replaced the condenser in the spring, from a leak I presume, I would add at least a 3 oz. can of ester oil. I imagine oil was added then, but how much? Part of the oil ends up sitting in the dryer, and I'm no expert, but for the cost I'd add it to the low side when running.

[486]
September 05, 2010, 15:17
See if you can jerry-rig another compressor into the place of the old one. There should be one that has a similar bolt pattern, and connectors can be welded up for cheap at a welding shop.

Of course, that is if all the local pick a part places don't have it. I only do refrigeration, no auto AC so I dunno, but usually when a compressor dies you wanna flush the system with denatured alcohol to get any gunk out, be it from burnt windings [on an electric hermetic compressor] or crappy bearings.

Eric Bryant
September 05, 2010, 22:04
Originally posted by Brett
Since you replaced the condenser in the spring, from a leak I presume, I would add at least a 3 oz. can of ester oil. I imagine oil was added then, but how much? Part of the oil ends up sitting in the dryer, and I'm no expert, but for the cost I'd add it to the low side when running.

GM systems with R-134a (pretty much anything newer than the mid-90s) use PAG 150 (high-viscosity) oil. A compressor change should be accompanied with an oil refill of about half the total system oil capacity - dump it into the "S" (suction) port prior to re-attaching the hoses to the new compressor.

Scott V2
September 05, 2010, 22:32
If I were to add a small can of oil to the low pressure side and it is already at a full charge, will I blow up the system? If I could limp this thing along until the Spring it would be best.

Brett
September 06, 2010, 03:16
Double check what I tell you, but from my experience too much charge (over 40lbs.) on the low side will cause bad compressor noise (as in seize). I don't know if that could be the problem to begin with. First thing I would do is check at least the low wide pressure on and off. Off should equalize with high side and on should drop to 35 or so. If low side doesn't increase considerably when off the compressor isn't working or there isn't enough freon for it to work. But you said the compressor is switching on so it has enough pressure to turn on. I don't think 3oz. of liquid put in the system will cause any problems unless you are already over pressurized. You can always let a little freon out to compensate ( I know, capture freon, so shoot me).

Scott V2
September 06, 2010, 10:23
I just stuck an el cheapo gauge on the low side and it shows it is over pressured. I will wait on adding any oil until I get this thing looked over.

Brett
September 06, 2010, 11:03
You need to check with someone who knows what the low side should carry pressure wise on a hot day. I'm thinking 45 lbs to be around the upper limit, but, like I said before, check with someone else first. Remember , it has to be running, otherwise it will show high.