Replacing the AC compressor in your vehicle is not too complicated, and you may consider it similar to replacing any other component on the motor, such as the power steering pump or the alternator. However, one key difference is that prior to actually removing the compressor, you will need to remove the connecting refrigerant lines.
You will see two lines: a low pressure line and a high pressure line. Before you go ahead with removing these two lines, you will first need to empty the refrigerant from the system. The high pressure side of your system may be more than 200 psi, while the lower pressure side may range from 30 to 60 psi.
Considering this level of pressure within the system, it can be dangerous to remove the lines when they are filled with refrigerant. Therefore, evacuating the refrigerant is first essential. Once you have emptied the system, removing these lines can be as easy as removing nuts and bolts.
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Steps to Replace AC Compressor in Your Vehicle are:
Step 1: Remove the Accessories and Air Intake
As a first step, unbolt and remove the hoses or tubing in order to access the serpentine belt. This tubing is meant for air filter intake and emissions, and can be removed quite simply by undoing a few minor screws or bolts. Once this is done, you should remove the serpentine belt that drives the compressor.
Step 2: Remove the Existing Compressor
Depending on your vehicle, the AC compressor might be in clear sight, or it could be buried under a layer of accessories and brackets such as the power steering pump or the alternator. Remove these additional accessories in order to gain access to the AC compressor. You can do this by loosening and removing the mounting bolts and wiring connectors.
Once the obstructions have been cleared, locate the electrical connector on the rear or front side of the compressor. This wiring is designed to energize the internal control valve (if it is found in the rear) or the engagement coil (if it is found in the front).
Use a screwdriver or a small pick to safely release the electrical connector. If you are unable to see the connector or find it hard to remove, you can do it after you have removed the mounting bolts from the compressor.
Thereafter, you should locate and take out the low and high side refrigerant line flare nuts or mounting bolts, depending on your model. (Some models may require you to carry out this step after the mounting bolts are off and the unit is loose).
Following the removal of the bolts, slowly pull upward the line bulkhead of each refrigerant line and disconnect. Once you have removed all the refrigerant lines and wiring harness connectors, identify and remove the upper and lower mounting bolts.
Make sure you grasp the unit firmly while you are taking out the last mounting bolt because the compressor unit is going to be slightly awkward and heavy to hold. So, you have to take care to avoid causing any injury to yourself or damage to the unit. Once the unit is completely loose, take it out from the engine bay.
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Step 3: Replace the O Ring Seals
The low and high side lines of the compressor housing are sealed with the O rings. It is important to keep these sealing surfaces free from damage or debris in order to prevent leakage. Use a pick or a small screwdriver to delicately take out the old O ring seals from the low and high side lines. Make sure the sealing surface where the O ring is placed is clean in order to ensure correct sealing.
Now match the new and old O rings, and watch out for their thickness because the diameter of some of the O rings can be different than others. It is prudent to avoid reusing the old seals as they would have become flattened with heat and pressure over time. If they leak, the job would have to be done again.
After cleaning and matching is done, you can install the new O ring seal on each of the high and low side fittings. After these are installed, you should apply a film of oil over the ring in order to prevent the installation from damage and avoid cutting the new seal.
Step 4: Install the New Compressor
At first, clear any lines or hoses while you gently lower the new AC compressor replacement inside the engine bay. Thereafter, hand thread in the bolts which will hold the compressor into its mounts. After you have hand threaded in all the mounting bolts, use a socket or wrench to tighten the bolts in a cross pattern evenly. This will ensure there is no distortion in the housing (which could result in premature failure).
Now take off the port dust covers and install the low and high side refrigerant lines with the bolts. You don’t need to tighten these bolts very hard, but just tighten them enough so that they do not come loose. Thereafter, you can reinstall the accessories (if any) by carefully lowering them into the engine bay.
Now hold back the serpentine belt tensioner as you reinstall the belt into position. After this is done, just review the belt alignment by examining the pulleys of every accessory and the drive pulley situated on the engine crankshaft.
Step 5: Complete the Reassembly
After the new AC compressor unit has been installed, it is time to finish the reassembly. Reinstall any hoses or tubes that you had removed during the process of replacement as well as tighten all the brackets, clips, screws, or bolts that you had previously removed or loosened. Once this is completed, your AC system is now ready to have a recharge service performed.
Do not fill the AC with refrigerant prior to the recharge service because the moisture would have entered the system when the system was opened. This seemingly minor error could cause the AC compressor of your car to fail premature or the unit may not perform as well as it should.
To understand in a better way How to Replace AC Compressor in Your Vehicle Watch the Video Carefully.