Working on my 2001 Cavalier 2.2 5-speed manual (265k) that has been in storage for the last 3 years. One of the things on the list is the AC system. The last time the compressor was on was probably around September of 2020 so almost 4 years ago. AC was perfect at that time. Well got around to checking things out and not surprisingly, no pressure, compressor didn’t kick on, hot air, etc…so first things first - in to Walmart for the can of r134a. Compressor kicked on and cold air. But it was dark and headlights are another issue - so only drove for about 15 minutes with AC on.
24 hours later, go out to check again - same as before I did anything - pressure too low to kick on compressor etc…Disappointing but not surprising. Even though I’ve done almost all the work on this car for the last 23 years - except replacing the clutch and the first compressor replacement many years ago - I am not really in a position to get involved with doing AC work, nor can I spend the money it would cost to replace the compressor.
My question is basically this. Assuming the shaft seal has dried out and is leaking (there were a few drops of oil below it when I was inspecting things after getting it to kick on), would it be worth adding either more refrigerant and/or an oil charge and then running it for much longer - like an hour or two - in an attempt to relubricate that seal and perhaps get it to the point where it might last days or weeks instead of 24 hours. I just need to get through the summer. Otherwise I just won’t have any AC I guess. Thanks.
I thought all those “stop leak” things were supposed to be avoided at all costs because they damage the system and create blockages/clogs. Has that changed? Is there a specific type that wouldn’t have this risk?
I can’t understand the seemingly disproportionate cost of AC work compared with other repairs. You can buy a whole compressor kit for like $200.
Lots of labor if it is done the right way. A shop doesn’t just throw on a new compressor. The whole system comes apart, all is cleaned, all new seals/o-rings, accumulator & drier, expansion valve… Then there’s also owning the appropriate equipment and knowing how to use it. The parts cost is the least of it.
Like Tester said, if all you want to do is see if you can eke a summer out of it, and never plan to actually repair it, then you lose nothing by trying out the stop leak. Right now, you don’t even know where the leak(s) is(are).
Since it sounds like you’ve been at least somewhat ambitious with fixing things up, you could just add dye, find the leaks and proceed from there.
Someone with the knowledge and equipment will need to do it
Replacing a typical ac compressor isn’t a 5-minute job
And if you need to replace an evaporator in your typical vehicle which requires removing the dash, it’s going to get REALLY expensive, due to the many hours of labor
As I believe I stated, I am familiar with every aspect of all components and repairs on this particular vehicle since I’ve been dealing with it for 23 years - including an exhaustive investigation into what was involved in the first compressor replacement and lengthy discussions with several mechanics at that time. I was simply stating my opinion that relative to other repairs, my opinion is that AC work is out of line with other costs.
Now back to my original question and the only reason I posted: "Assuming the shaft seal has dried out and is leaking (there were a few drops of oil below it when I was inspecting things after getting it to kick on), would it be worth adding either more refrigerant and/or an oil charge and then running it for much longer - like an hour or two - in an attempt to relubricate that seal and perhaps get it to the point where it might last days or weeks instead of 24 hours. "
The reason I ask here is that I first asked several other people and that was their suggestion, given the parameters I explained.
And I like the way you stated your opinion rather respectfully, versus some other guys on this website, who continuously allude to theft, overcharging, dishonesty, etc.
It’s possible to have a civilized conversation with you, unlike some of those other guys
You have to remember that the AC system contains refrigerant and that gas is regulated by State and Federal environmental laws. Any licensed repair shop is obliged to have the equipment and personnel to comply with those rules, or risk penalties, fines and loss of its license. There are other parts of a car that are regulated, but this one is somewhat special. Lots of law enforcement interest here. If you buy parts and do the work under a tree in your side yard there are none of those controls or ways to punish you.
And skilled technicians and their businesses deserve to be paid a decent living.
I forgot this is the internet - where everything has to be an argument. Nobody said anything about overcharging, ripping people off, etc…nobody said anything about how mechanics make too much money, etc… I came here to ask a very simple, straightforward question and as an aside, happened to mention my observation about pricing for AC work compared to other systems. I am aware of everything that has been written. There is no new information here and it does not change my opinion.
Still haven’t seen anyone answer the question, though.
The loss of refrigerant in 24 hours is a significant leak, this will need to be repaired. An experienced technician should be able to identify the leak in a short amount of time.
There are generally 4 to 8 ounces of refrigerant oil in the system to lubricate the compressor, more oil is unlikely to help the leak. The compressor shaft seal in not made of rubber, it is made of a hard material. A film of oil helps seal the contact area of the shaft seal, 10 seconds of operation will distribute oil, so 15 minutes was plenty of time.
Here’s the thing…a licensed technician, such as myself, is required to follow the Clean Air Act. A do-it-yourselfer working on his own vehicle, or home A/C, or self-contained appliance, etc. does not need to worry about things like maximum allowable leak rates, proper recovery of refrigerant, etc.
A DIYer can simply add refrigerant as needed, no matter how often it must be refilled again. A DIYer can also just let the refrigerant out, swap the defective compressor (or other parts), pull a vacuum, and recharge.
So comparing what a professional shop/professional service company would charge to the online price of parts which a DIYer would pay is not realistic. That being said, if cost is a major concern, paying for professional labor and expertise might very well be out of the question. In that case, I’d recommend to not use sealant, just add dye and refrigerant, and hopefully you will be able to find whatever is leaking. Then, you can go ahead and drain the system, swap out the defective part(s), evacuate, and recharge…all at a price that you can afford.
What if OP added 2 ounces of AC oil, and monitored the situation to see if the AC performance improved and lasted? Worth a try? Or a waste of time? Or worse than doing nothing?
No AC experience myself . I expect the best solution is to just have the AC system rebuilt/repaired by a qualified AC specialist shop.
Refrigerant oil is unlikely to help you. The rubber seal has deteriorated and just adding more won’t fill in the cracks. System pressure will push the oil out again. You need something to swell the seal and the stop leak will provide that. The swelling comes from partially dissolving the seal, allowing it to absorb the stop leak. While the stop leak will eventually create an unsealable leak, it should last through the summer.
