Easy Steps on How to Install an AC Compressor Bypass Pulley

Last updated on January 13th, 2023 at 08:24 pm

You may be wondering what an AC bypass pulley is and what it does. Or You may also be needing some Easy steps on how to install an AC Compressor Bypass pulley. If you are not a car owner, the chances you may know are quite slim. An AC bypass pulley is a mechanical tool which is used or installed into a car when you want to remove or bypass the factory AC system. This typically happens when the factory AC system is faulty or completely bad.

What does  an AC Bypass Pulley Do?

Just knowing what they mean is not enough. An AC bypass pulley is a tool that helps you to run the AC without the AC compressor in the car. There are several benefits of the AC bypass pulley one of which is it’s cost benefits. It is exceedingly cheap in comparison to the AC compressor if you try to replace it. The price difference is just too much.

How to Install AC Compressor Bypass Pulley

Now you know what  they are, how do you install AC Compressor Bypass Pulley. To install AC bypass pulleys you naturally need to have bought the Bypass pulleys first. They can be found at

The prices range between $35 to $50.

Please note that when you buy the bypass pulley you also have to buy a bypass belt.

Here are some steps on how to install AC Compressor Bypass Pulley. This may vary according to vehicles.

  1. You have to remove the connectors from the compressor
  2. Then you remove the bolts and disconnect all AC lines from the compressor.
  3. Then remove the AC compressor. You can insert bushings into the mounting holes where necessary.
  4. Insert bolts through the mounting holes with bushings to centre bracket and securely tighten it.
  5. Install serpentine belt and check for proper fit

But in case the serpentine belt doesn’t sit properly on the pulley follow these additional steps.

  • Remove the serpentine belt as well as the bolt holding the pulley to the bracket and remove the pulley.
  • Place a washer behind the pulley or bracket. This washer will provide the space needed for the belt to ride properly on the pulley.
  • Then you can reinstall the pulley.

How to fix AC compressor clutch

The AC compressor pulley is an amazing alternative. But what if you want to fix the AC compressor clutch?

The AC compressor clutch is a small mechanical device that consists of the clutch plate,  pulley and clutch coil. It is used to connect and disconnect drive power to the car’s AC compressor shaft.

The compressor clutch coil is simply a large coil of copper wire. When the driver requests AC, the system provides power to the clutch coil, thereby generating a magnetic field.

The clutch plate connects to the AC compressor shaft and drives the compressor when it mates against the clutch body

When the clutch coil receives power, it generates a magnetic field and then pulls a portion of the clutch plate against the clutch body/pulley, causing it to rotate the compressor shaft. Be sure to check out this post on my top picks on the 7 Best Power Steering Pulley Puller

Unlike a car’s transmission clutch, an AC compressor clutch is always transmitting full power. A slipping AC compressor clutch is a sign of severe wear. You need to know that if the clutch doesn’t engage with the compressor, the pump will not work.

When that happens, there will be no coolant or refrigerant that will go around the air conditioning system to cool your car. This simply means the AC won’t work.

So, if your AC compressor clutch has gone bad, not to worry. There is still hope. It can be fixed.

Here are some steps to take on how to fix an AC compressor Clutch;

  • Loosen the bolt that holds the clutch assembly together. It is usually a 10mm bolt. The reason why it is so tight is so that it doesn’t get loose from vibrations while working.
  • Use a plier to gently remove the clip (protect your eyes while removing this one, it tends to fly out.)
  • You can then remove the old and worn bearing from the clutch pulley. To do this, you can put a 36mm socket into the middle of the pulley to help remove the bearing. You can the use a gear puller up there.
  • You can then heat the AC pullet up with a heat gun to enable the new bearing to enter easily.
  • Afterwards, install the new bearing into the pulley using the gear puller.
  • When this is done, couple it back together on the AC compressor using the 10mm bolt you removed earlier.

Related article: How To Remove Power Steering Pump Pulley Without Puller

How to replace AC compressor

If the clutch however is too faulty, it is advisable to just get a new one.

The situation may even be beyond just the AC compressor clutch. If the AC compressor is faulty and you need help on how to replace AC compressor, you can follow the steps below.

  • Pry on the fan belt tensioner and pull the fan belt off
  • Unbolt the compressor using a spanner. If there are obstacles like power steering pump or alternator, you can remove them by loosening and removing wiring connectors and mounting bolts.
  • Locate and remove high and low side refrigerant line mounting bolts.
  • Remove all the electrical wiring
  • Bring out the old compressor.
  • Pour 4 ounces of oil in the new compressor
  • Couple it together and put in the car.
  • Put back the refrigerant lines and all the electrical connections.
  • You may then use a vacuum pump to remove excess moisture from the AC system.
  • While the vacuum pump is running you can put back the fan belt.

          Those are simple stepson how to replace AC Compressor.

Why AC compressor wont engage

An AC usually comes direct from the manufacturers of a car. It is a pretty common feature of modern cars. Sometimes in the course of using the car, your AC may stop working. It may be that the AC compressor won’t engage. There are a number of reasons why an AC Compressor wont engage.

  • A blown fuse
  • An open in the wire to the clutch coil
  • A bad compressor clutch coil
  • A poor ground or a low pressure lockout.

Unfortunately you may not really be able to tell exactly what the problem is without unbolting the mechanical equipment to examine. You may experience your AC blowing warm air or not coming on at all when the AC compressor won’t engage. In other words, you need to always find out why an AC compressor won’t engage before seeking other ways to fix it.

Sharing is caring!

Scroll to Top