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I’m helping out a friend with her 07 Subaru Impreza. She told me that the belts on her car were squealing badly. I had her bring it in and I put 2 belts on. One belt was split right down the middle with half of it missing. She left and 2 days later said it was doing it again. She then tighten up the belts herself as I talked her through it on the phone. The next day, she called again and said the same thing was happening. After we talked for awhile, I had her look at the belts as they made the noise. It wasn’t the belts. It was the A/C. The A/C clutch was engaging but the compressor wasn’t turning with it. She brought it in so I could look at it and it was working fine. I turned it off, then on, and it did the same thing. The clutch engages, but the compressor turns very slowly. Turned off the car and the A/C and tried turning the compressor. I could bearly turn it at all. I was thinking it was bearing. Got a used compressor off of a newer car with 12k on it. Took off the old 1 but couldn’t see any signs of damage. Nothing in the lines or in the openings of the compressor. I did not flush the system for that reason and, I do not have the equipment to do it. Put on the used 1, recharged it (yes, evac and all) and it worked great. Three days later, same thing. I’ve recharge hundreds and hundreds of A/C systems but do not get into repairing them. I work in the auto collision field. So my guess is that maybe the expansion vavle isn’t working correctly and blocking the flow of freon. I have no idea if that can even happen, but like I said, sometimes it works fine. Can anyone help me out with this? She’s has no money and I don’t won’t to send her somewhere and have to pay big bucks. The 2 times I had the gauges on the car eveything was working fine. Don’t remember the numbers exactly, but they were ok. Thanks, John
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If the belt has the correct tension and is not
slipping. you weighed the refrigerant charge (I hope)
you have another bad compressor or clutch bearing.
if there was a restriction the compressor should not
run due to the LP switch. If it were over charged the
high pressure switch would stop the compressor.if it has one.
you would see the pressures go crazy high. The only thing I
could say is you used a unknown condition compressor.
For now take the belt off so she can drive the car.[quote=”RIDETHEREJK” post=31395]I’m helping out a friend with her 07 Subaru Impreza. She told me that the belts on her car were squealing badly. I had her bring it in and I put 2 belts on. One belt was split right down the middle with half of it missing. She left and 2 days later said it was doing it again. She then tighten up the belts herself as I talked her through it on the phone. The next day, she called again and said the same thing was happening. After we talked for awhile, I had her look at the belts as they made the noise. It wasn’t the belts. It was the A/C. The A/C clutch was engaging but the compressor wasn’t turning with it. She brought it in so I could look at it and it was working fine. I turned it off, then on, and it did the same thing. The clutch engages, but the compressor turns very slowly. Turned off the car and the A/C and tried turning the compressor. I could bearly turn it at all. I was thinking it was bearing. Got a used compressor off of a newer car with 12k on it. Took off the old 1 but couldn’t see any signs of damage. Nothing in the lines or in the openings of the compressor. I did not flush the system for that reason and, I do not have the equipment to do it. Put on the used 1, recharged it (yes, evac and all) and it worked great. Three days later, same thing. I’ve recharge hundreds and hundreds of A/C systems but do not get into repairing them. I work in the auto collision field. So my guess is that maybe the expansion vavle isn’t working correctly and blocking the flow of freon. I have no idea if that can even happen, but like I said, sometimes it works fine. Can anyone help me out with this? She’s has no money and I don’t won’t to send her somewhere and have to pay big bucks. The 2 times I had the gauges on the car eveything was working fine. Don’t remember the numbers exactly, but they were ok. Thanks, John[/quote]
Do the belts squeal with the car running and the A/C off?
If you want to text or email me a land line number where I could call you and a good time to call I can call you about this. My contact info is below in my signature.
No, when the A/C is off, the belts don’t squeal. The pulley spins free as long as the A/C is off. The noise is more of a screaching from the clutch slipping but she thought it was the belts. I put 1 lb. 3 oz. in the system wich I believe is correct. I say believe because the car is not in front of me and it’s hard for her to get time off for me to look at it. Both times I had the guages on it, it ran fine and the pressures were ok. I haven’t been able to put the guages on it while it’s not spinning. I will have her read the information label and tell me what it says, but I’m sure it’s right. When the A/C worked and was charged, both old and used, you could spin the compressor by hand. But when the A/C didn’t work, it’s hard to spin them. It’s not like a grinding feel. It’s hard to explain how it feels. If you have ever put a motorcycle in gear with the rear wheel off the ground and spun the engine using the tire, then you have an idea of what it feels like. And both compressors feel and act exactly alike. Sure, it’s a used and “unknown” compressor, but I would find it hard to believe that both of them act and feel the same. I’m not saying it can’t be or wont be, just odd. I trust the guy I ordered the compressor from. Been working with and friends with him for years, so I know he didn’t lie about the mileage or condition. I can always call him and get another, but I really think that it’s not the compressor. But, that’s why I’m here. I want to find out what the people that do this all the time think. One more thing, with the old compressor, when it had a charge but couldn’t spin it, as soon as I recovered the freon, I could spin it again. Don’t know if that changes anything or not.
johnbkobb, I will email you my info, thanks to everyone trying to help. John
Did you try to free-wheel all the pulleys to see if you have any issues there apart from the Ac/C compressor?
I would also check for belt alignment.
Keep us posted.
The label says it holds .55 kg. That comes out to 19.4 oz. I put 1 lb 3 oz. in. So unles the label is wrong, it shouldn’t be over charged.
[quote=”RIDETHEREJK” post=31395]So my guess is that maybe the expansion vavle isn’t working correctly and blocking the flow of freon. I have no idea if that can even happen, but like I said, sometimes it works fine.[/quote]
I am new to AC work…
Shouldn’t a good compressor with good bearings spin freely regardless of the amount of freon in the system?
The belts and pulleys are fine. The noise is the clutch slipping against the pulley because the compressor is very hard to turn.
I would think that a good compressor should turn also. This is why I was thinking that there may be some kind of blockage. Pumping liquid through a small hole is harder than pumping air.
I did talk with johnbkobb tonight and he helped out a lot. Long story short, he believes that the first compressor failed and not flushing the system caused the second one to fail also. I didn’t see any debris in the lines or the old compressor but who knows.
She is trying to get the car back to me so I can have it for a couple of days. I will keep you all up to date. It helps no one not to report what fixes a problem.
It’s possible that when the first compressor went it sent debris into the system. Anytime you have a locked up compressor you need to flush the system out. You should also properly evacuate the system before opening it to replace any parts. It may be that the expansion valve is clogged with debris in which case it will either have to be replaced or removed and cleaned and the system flushed out.
In my experience AC work is rarely cut and dried so you’re not alone in what you’re going through.
On Friday, she was able to give me her car for a few days. I asked her if she has tried to use the A/C at all and she said no. I turned it and wouldn’t you know, it worked. I ran the car for about 1.5 hours with the A/C on. I wrote down the RPM, temperature, pressure readings, and the temperature at the vent. I forgot the paper at work but remember some. Will post the exact numbers tomorrow. For .5 hr., I ran the car at 1750-1900 RPM. The temperature was about 85 F. The pressures read between 275-250 high side, and 19-18 low side. The temperature at the vent with the A/C set on fresh air, coldest setting, fan speed on the 2nd of 4 dots was about 46 F. I then raised the RPM to 2000-2200 for another .5 hr. The pressures went to about 300-275 high side, 18-16 low side. The temperature was still right about 45-46 F. As the compressor cycles on, the high side spikes at the higher number and moves slowly down to the lower one. As it cycles off, it lowers much further but don’t remember the pressures at rest at all, but like I said, I will post them tomorrow. At this point, I removed the gauges so I could drive the car home, but left the car running with the A/C on. I drove the car home which took another .5 hr. and the car stayed cold and ran quiet. Saturday morning, I went out and started the car. I turned on the A/C and again, it ran just fine for about 10 mins. I turned the A/C off, then the car, and then thought that she never turns off the A/C. So I started the car, turned on the A/C, and then shut it off. About 2 hrs. later, I went out and started the car. I got an immediate screech from the clutch on the compressor. It was turning very slowly. (not sure if that means something or not, but at least I might have found a way to make it happen after I think I fixed it) I shut off the A/C and drove it to the shop. I opened the hood, turned on the A/C, and it worked fine again. I then shut everything off. I could turn the clutch by hand (the clutch turns the compressor) but it was hard, like it was building up pressure. So I decided to evacuate the system, and can now spin the clutch by hand very easily. I took off both lines that go into the compressor and wiped them and the holes with Q-tips to see if there was any debris inside. I used a new Q-tip on each hole and the only thing that was on them was oil with dye. No dirt, metal, or anything else. I put the lines back on and pulled a vacuum. The car is still holding a vacuum 48 hrs. later. I still have not replaced any other parts yet. If it is a bad compressor and there is stuff floating around in there, I don’t want to ruin the new parts. I guess I’ll try and take out the expansion valve. The lines at the firewall are easy to get to and I’m hoping the valve will be sitting right there waiting to come out. I really don’t want to have to take the evaporator out.
Does this help anyone in thinking what might be wrong?
Thanks to all that are trying to help. I really appreciate it. JohnDon’t forget that the accumulator should be changed if you open the system. To help to remove any moisture/air that may have gotten into the system.
Yes, I plan on changing it, but I want to find out what the problem is first. I don’t think that is what the problem is. I’m thinking the valve first.
Hello,
What it sounds like to me is there might be too much oil in the system.What I think I would do is take the compressor off,take it back to get another used one,most places offer atleast a 30 warranty on used parts.Next thing is I would flush the condensor,all you need is some “Non-Clorinated brake cleaner” and a air hose.Make sure to flush it in both directions,blow it out good.When you get the other used compressor drain all the oil out of it by spinning the clutch while dumping it upside down.Look up the spec for the compressor and and add 1 oz. lower then it calls for,that will compensate whats still in the evap and lines.I always put new o-rings on,which I am sure you did,I also agree with john on changing the receiver/dryer,as it gets pretty full of moister and oil,After you vaccum it down,i usually do it for around 45 minutes,do a slow charge on the system.What I mean by that is put a temp gauge in the vent and slowly add some freon,let the car run for around 5 minutes for the freon to get circulated through the system.Only add enough freon till its blowing at around 45-50 degrees.I think it should have a site glass,watch of low to no bubbles.I had a lexus come in the shop that had a slipping clutch issue as you described,slow charged it,took me about 25 to 30 minutes,and its been blowing cold ever since,2 years now.Hope some of this help ya.If you need the specs on the system,send me a message,I would be happy to help,,,odieIt could be the clutch clearance is not set correctly. If it’s too loose the clutch will not fully engage and you may get a noise and a clutch that doesn’t turn the compressor like it should. The next time that happens see if you can turn the compressor by hand, if you can then perhaps this is the case. I would then check the clutch clearance and compare it to spec. I don’t know the exact spec but I would say that .045 is a good number to start with. If it’s more than that or you see signs that the clutch is burned up then this may be your problem. Normally you set clearance by installing or removing shims from under the clutch mounting bolt. All of this can be done without opening the system as the clutch is external to the compressor. One other possibility is an electrical issue with the stator. If it has a short in the winding or something it won’t be able to put enough magnetic force on the clutch and it won’t fully engage. I would look for a mechanical issue first however.
Well, I took the lines off at the firewall. Used a camera snake to look into the expansion vale. It looked clean and free of any debris. I wanted to somehow loop the two lines and fill up the system with the evaporator not connected. Like I have said before, with no pressure in the lines, I can spin the compressor by hand, but with pressure it it, I can’t. I was thinking that if I could spin the compressor with refridgerant in it without the evaporator hooked up, then that would be a really good sign that the expansion valve is bad. So I took a hose that fit on the high side line at the firewall and clamped it on. Then took a larger hose that fit on the low side line and clamped that. I put the smaller hose in the larger hose, clamped it, and pulled a vacuum. I really didn’t think it would work, but it did. I onlt put 10oz. in it, but I could spin the compressor by hand. The day before, with 13oz. in, and the evaporator hooked up, I could not. I have an expansion valve coming tomorrow and will see what happens. I took the old one out and it looks clean. I’ve never seen one before, but there was no marks, dirt, metal, or anything present. I removed the cap on the bottom that holds a spring on a plunger and it all looked fine. I’m hoping that the thermastat that opens and closes the plunger is just bad like in when it happens a coolant system. I have my fingers crossed.
Eric, I have not checked the clearance on the clutch. I figured that since I can’t spin it by hand, the clearance isn’t the problem.
odie241, I will try that out if this doesn’t work.
It just seems really odd that both these compressors do the same thing and there is no signs at all of any wear from inside the system. I’m hoping that the expansion valve was the cause in the first place. I’m trying to make time to get it done tomorrow. She has to leave Tuesday for AZ. She’ll be there for at least a month or so but might stay for good. Wish me luck.
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