AC Delco Compressor - How to Replace your Compressor

Temperatures are on the rise again, and summer's just around the corner. In my neck of the woods, the temperature is hot enough for shorts and short sleeves. If your car's AC compressor went out, now's the time to get it replaced before you're sticking to the seats this summer.

Having done this before, it's possible to perform this repair at home on your own vehicle. I went with an AC Delco compressor. The AC Delco was my choice for a few reasons:

1. They're part of the GM family
2. I could trust that the part would fit correctly
3. AC Delco parts are quality
4. I knew that if something went wrong with the part itself the company a) would honor the warranty and b) was not fly-by-night
5. The company has been open for over 90 years
6. I've had good success with ACDelco parts before
7. For the price, i got a good combination of quality and value

You can find AC Delco compressors online at Amazon, which is where I bought mine. Amazon offers free shipping on this, so if you've got time & temperatures are killing you yet, you may want to consider ordering from them & saving a few bucks.

AC Delco also makes parts for other makes. You can buy ACDelco parts for your Acura, BMW, Dodge, Ford, Honda, Hyuandai, Jeep, Kia, Lincoln, Mazda, Nissan, Toyota, just to name a few, so you can consider using an AC Delco compressor in your repair.

I've made sure that this compressor replacement how-to translates to every vehicle, so I'll outline the process and leave it up to you to get under the hood and work out the details.  It should be applicable for any make or model.  Having a repair manual around is going to be a lifesaver.

I also assume that you have a general knowledge of the various parts in a car's AC system.  This article is focusing on replacing the compressor & the steps that are involved.

You'll need to discharge the freon in your AC system before you can install your new AC Delco compressor.  Freon is hazardous to the environment & must be handled properly.  You should have a professional do this, as they have special equipment to store the used freon.

After discharge, remove the belt that's on the AC clutch.  It's best here to just remove the belt from this one accessory.  If you do remove the belt entirely, there are usually diagrams within the engine compartment that will show you the proper routing of the belt.

Somewhere on the compressor, you'll find an electrical connector you'll need to disconnect.  This switch operates the clutch, turning the compressor on and off.  Disconnecting the negative side of the battery to prevent shock is a good precaution.

The hosing attached to your AC compressor must be removed.  A common setup to see on the compressor is a single bolt holding the high and low pressure lines on.  Plug the lines after removal.  Getting any foreign material into the AC system will cause damage, which is why we plug the system when it's open.

Unbolt the compressor from the accessory bracket.

Re-installation is somewhat the reverse.

Attach the AC Delco compressor to the stock accessory bracket.  You may want the repair manual here to reference any torque specs.  In the absence of one, make sure that it's secured tightly by hand.

Reconnect the high/low hoses.

Reconnect the electrical for the clutch.

Re-install the belt, using the diagrams in the compartment.

Now you have to recharge the system.  You can have a professional do this as well, but it can be done at home to save money.

You will need to make sure that you attach a vacuum to the system to remove any air/moisture that was allowed in during the replacement of your compressor.  You cannot skip the above, as it can cause your new AC Delco compressor to fail.  Allow the vacuum to run between 15-30 minutes, depending on how long the system was open.

You'll recharge with r134a while running the AC & the engine. 

If you have a gauge to measure system pressure, fill the system with 30-40psi of freon while the engine is running around 1500rpm.

To do this without a gauge, just fill the system at 1500rpm, holding the low pressure tube coming out of the firewall, until you feel it get very cold.  Then stop.. 

You'll want someone to help you, especially if you're not using a gauge.

It's done.  You should now have your new compressor installed and ready for the hot summer.