Used parts vs new


I’m looking to replace my a/c compressor and found one used for $65 - there’s quite a few of them out there for under $100. I would like to buy one of these and pay a mechanic to install it for me. This is an old 93 Dodge Shadow with 218K miles and I am trying to replace it, thus the attempt to minimize my repair bills. I want to find out, though, if this is one of those parts that should not be installed used. The mechanic is going to charge around $180 to do the work for me.


Used parts are always a crap shoot whether it’s a compressor or anything else.
Salvage yards “guarantee” these parts to be good, but if they’re not the yard is off the hook no matter what as to labor involved in the installation of those parts.

I’ve installed a number of used compressors and had good luck. One thing I would recommend is that you grasp the center center section of the clutch and rotate it a number of times by hand. You should feel the compressor turn smoothly.
JMHO on this one, but I always install a new shaft seal kit on a used compressor.
The compressor is already laid out there and it’s much better to do it then rather than install the compressor and then find out it’s leaking. Most compressor leaks are caused by the shaft seals anyway.

You might check the compressor around the clutch area for oil leakage. Refrigerant loss over time always takes some oil with it and you never really know how much oil has been lost in the past.

Before replacing anything though, I would want to put a set of gauges on it and see what’s going on inside the system.


Hi and thanks for the reply. Could you clarify your last sentence - put a set of gauges on what? The used part I buy or the currently-installed part and the rest of the a/c system (which is currently working fine)?


OK4450 knows a whole lot more than I do, but when he said “I’ve installed a number of used compressors and had good luck,” I wanted to add my 2-cents. I’ve tried a couple of used compressors, and had very bad luck – they were both on the same car. When the second one failed I gave up and tried a rebuilt from Autozone or Advanced Auto Parts. And that one leaked, too. It’s replacement did work for a while. By the time I paid my cheap-but-good mechanic for four compressor changes, I’d have been ahead with a dealer’s new one.

It is, indeed, a crap shoot.


That’s my experience too. I put used and got about 50K on it, then rebuilt for about 100K, and then new which are good for 200K plus if cared for. You never know on a used one plus its all the labor for the work and the cost of the system cleaner, freon, new dryer and so on. I guess if you don’t expect to use it much and won’t fix it if it goes again, maybe. I’d try to get one that was lower mileage though.


I would probably shop around for a rebuilt instead of used because the installation cost is more than the hardware, especially if you are planning on keeping the cr for any length of time.


Hmmm. Yes I have thought about the scenario where I pay to have a used compressor installed only to have it break again and am not sure. It is a car with 218K miles on it, and I am trying to save up to replace it. Justifying a new or even rebuilt compressor is tough at this stage. It is a hard decision to make. Still, I will shop around some more for a rebuilt one.


What will happen if the compressor freezes up completely or breaks while I am en route somewhere? Will the car still be drivable or not? I’m not sure what else that belt drives…


I guess it comes down to cost, hopefully you can find a rebuilt one that’s closer to the cost of a used one than a new one.


I only mentioned the gauges since the clutch problem you mentioned in the other post sounded a bit odd. Knowing the high and low pressures helps in figuring out things.

Assuming the clutch is bad and you decide to go with a rebuilt compressor I would advise staying away from the Four Seasons rebuilds. I’ve seen a few problem ones, including 2 bad rebuilds in a row I got on the same car. Both compressors were horribly noisy and it appeared the rebuild was probably nothing more than cleaning, new seals, and a fresh coat of paint.
And yes, the system had the proper amount of oil.

I would actually not have a problem with a salvage yard compressor if it is known to be a fairly low mileage unit; say in the 50-70k miles range.


If the A/C compressor is in doubt, don’t run the A/C as you drive the the mechanic. This will prevent any additional damage to the compressor.

Also, check to see what other accesories are driven by the belt with the A/C. I have one car that the A/C compressor is the only thing on the belt, and another car that shares all the accessories on a single serpentine belt. It really is model dependant.


I only spoke about mileage with one salvage yard, but their three compressors were all above 100K miles, leading me to believe that at this late date a lower mileage compressor would be a rare (but nice!) find. I’ve decided to install a new clutch instead - for now. If that fixes the problem, I’ll be way ahead monetarily.


I guess this is somewhat off the topic but depending on what climate you live in you might want to consider one of those small 12 volt fans. I have survived many summers without AC.


The part will be a crap shoot. However a 93 Shadow with 218k miles is also a crap shoot on how long till a major repair far exceeds the value(very low and easy to surpass) of the vehicle and to yourself.

I would use a used part in the car for AC.