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How to Replace an Idler Pulley

How to Replace an Idler Pulley

Idler pulleys are responsible for guiding the engine belt of a vehicle. This belt, then, is responsible for the working of engine accessories including power steering pump, the AC compressor, water pump, and the alternator.

Since an idler pulley is essential for the working of your vehicle’s belt system, it is important to pay attention to its wear and tear, and get it fixed and/or replaced, if needed. You might wonder how you’re going to figure that is the time for idle pulley replacement. In this article, we’ll have a look at some symptoms that show that your idle pulley needs replacement. Further, we’ll also provide you with a short guide on how to replace your worn-out idle pulley.

Bad Idler Pulley Symptoms

The following pointers indicate that your car has a bad idle pulley which must be replaced on an urgent basis. Let’s have a look:

1. Belt Squealing

A high-pitched squealing sound coming from your car indicates that your idle pulley has completed its useful life and it’s time to change it. This class idle pulley noise indicates that all is not well with your car’s engine’s component.

2. Visibly Worn Pulleys

If you are the type of person who regularly checks their car before going on a ride, you will easily detect the signs of wear and tear on the pulley. Visible scuff marks on the surface of the pulley show that now you should go for idle pulley replacement.  

3. Damaged Pulley

In serious cases, the worn-out pulley will eventually break or crack. In other cases, the belt may fall off of the engine. An engine without a belt will encounter the issues of stalling and overheating. If such a situation arises, get your idler pulley replaced immediately.

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Is It Safe to Drive with a Bad Idler Pulley?

People often ask, how long can you drive with a bad idle pulley? An idle pulley, as discussed above, is an important component of your car. And it is clearly not advisable to keep driving the car while knowing that there is something wrong with the pulley.

Hypothetically, a car with a bad idler pulley can run for months or only few days. The best thing is not to jeopardize your life while driving a car with a bad idle pulley. Take your car to the nearest car repair shop and get the pulley fixed in a timely manner.

Idler Pulley Replacement

In this section, we’ll explore how to replace an idler pulley. Not that we convince people to carry out a DIY car project, but we see no harm in sharing tips regarding idler pulley replacement. Obviously, in extreme cases, you cannot follow these steps and ought to take your car to the car shop and let the professionals handle it. However, if you have a small problem, you can easily replace the idle pulley on your own. Read on to find out how:

Materials Needed

You’ll need the following materials to get started:

  • Replacement idler pulley
  • Socket set and ratchet
  • Torque wrench

Step-By-Step Guide to Idler Pulley Replacement

1. Disconnect the Battery

Before you begin working on the idler pulley replacement, you have to ensure your safety. On this basis, the first step that you ought to take it to disconnect the battery so as to cut power to the battery. Keep the cable at a safe place where it doesn’t come in contact with anything metal.

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2. Remove the Drive Belt

The next step is to remove the drive belt. For that, release the tension to the belt. In case your pulley is attached to the engine block you will have to loosen the bolt that is attached to the engine block to relieve the tension. Once this step is done, push the pulley back and release the drive belt. Repeat the same process if your pulley is attached to the alternator. Once the bolt is removed, push the alternator down to release the tension.

3. Remove the Old Pulley

The next step is to release the old pulley Be careful of the hardware that comes off and keeps it safe as you will need them to install the new pulley.

4. Install the New Pulley

This is a no-brainer. Once you have removed the old pulley, the next step is to install a new one. Use the hardware (bolts and gaskets) from the old pulley – in case the existing one didn’t come with a set of its own and install the new place in the same order as the old one. Tighten the retaining bolt, once the pulley and hardware are well in place.

5. Torque the Pulley

Use a torque wrench to torque the pulley bolt to 40ft/lb.

6. The Final Steps

Replace any plastic shields or covers that you had removed while accessing the drive belt. After that, connect the battery cable.

The Final Word

Replacing the idler pulley sounds too easy. Well, it is if the problem is not grave. In case of serious problems, always reach out to an expert.

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