Disconnect the negative battery cable.Loosen the tension adjustment bolt with a socket wrench and remove the drive belt. … Remove the retaining bolt to release the idler pulley. … Compare your old idler pulley with your new pulley to check you have the correct replacement.

How do you replace the idler?

Slide the belt off the idler pulley. Hold the idler pulley so it cannot turn and loosen the center bolt with a socket wrench. Remove the bolt completely and pull the idler pulley from the engine. Installation is the reverse of removal; however, make sure you torque the center bolt of the idler pulley to 40 lbs.

How long does it take to change an idler pulley?

If you are doing the job at home, give yourself about four hours to change all the parts. You will need the following tools and parts: Replacement idler pulley.

Are idler pulleys reverse thread?

If it’s just an idler pulley it’s standard. If it’s a tensioner pulley it may be reverse thread depending on the way you need to move the pulley to unload it.

Is a tensioner pulley the same as an idler pulley?

The primary distinction between tensioners and idler pulleys is the presence of an adjustable bolt. Tensioners are positioned on the bolt through mounting. Idler pulleys are not mounted to an adjustable bolt. … However, if bearings fail, tensioner and idler pulleys both require replacement.

Can you drive without an idler pulley?

So, how long can you drive with a bad idler pulley? The safety recommendation is not to drive the car at all and take it to a mechanic immediately. You should be concerned if the vehicle makes squeaking or rattling noises. The car can still run for months or break after a few days.

Is a tensioner pulley bolt reverse thread?

The PULLEY bolt on the tensioner is left hand thread (turn clockwise to loosen) but the bolt that retains the tensioner to the alternator bracket is standard right hand thread (turn counter-clockwise to loosen). If you are trying to remove the tensioner from the bracket it just takes a little muscle.

What are the symptoms of a bad idler pulley?

• Chattering, Squealing, or Chirping Sound. …
• Corroded Surface. …
• Excessively Loose Idler Pulley. …
• A Bad Idler Pulley May Spin Excessively. …
• Slow to No Spin or Binding.

What does the idler pulley do?

The idler pulley is a common part that’s found on the majority of the vehicles on the road. Its primary function is to provide tension and guide the engine drive belt. These belts wrap around the various parts of the engine such as the power steering pump, alternator, water pump etc…

Should I replace idler pulley?

If there is any wobble, squeak, or undue friction, the idler pulley should be replaced. The best way to maximize the idler pulley’s lifespan is to maintain proper tension on the serpentine belt and replace belts with new ones whenever required.

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Does a idler pulley make noise?

Most vehicles only need one idler pulley for the engine. … One easily noticeable symptom is a squealing or other strange noise coming from the engine area. This will likely be the beginning stages of idler pulley problems or problems with the serpentine belt.

How do you disassemble a tensioner pulley?

Put a socket on the bolt and turn the bolt counterclockwise to break it loose. If it will not break loose because the tensioner wants to move, keep the tensioner from moving by holding it in place with a pry bar; then you will be able to loosen the bolt in the pulley.

What does a worn idler pulley sound like?

When the grooves on the belts are not holding on to the pulleys, you will hear a noise coming from the engine. They will make a rattling sound if the bearings are worn out. They will remove the belt from the pulley and try to move it on their own. …

Is the idler pulley attached to the tensioner?

An idler pulley is a bearing with a pulley that changes the direction of motion of a belt. It is generally fixed in position. A tensioner is an idler pully that is mounted on a moveable mount so that it maintains tension on a belt.

Why is it called idler pulley?

The idler pulley is aptly named because it does just that: idles. Unlike drive pulleys, which are driven by a motor and a shaft, the idler pulley doesn’t turn on its own power. The crankshaft pulley, alternator pulley, power steering pump pulley, and the air compressor pulleys are all drive pulleys.

Why do idler pulleys go bad?

Every idler pulley ages as time progresses simply because it spins along the belt, creating wear on each part. Such wear decreases tension that can cause significant belt slippage.

Can a bad idler pulley cause alternator problems?

Alternators are DRIVEN by the serpentine belt. All that happens when the belt disappears or pulleys seize is the alternator stops turning; there is NO possibility of damage to the alternator.

Where is idler pulley located?

Idler Pulley Location The idler pulley and belt are located near the front of the engine. You will see the belt rotating in conjunction with the engine. You can find the idler pulley when you look at the serpentine belt moving on the engine.

Should I replace the tensioner or just the pulley?

If the pulley is damaged, replace the tensioner assembly not just the pulley. If an idler pulley is damaged, inspect the tensioner also because vibrations caused by a bad idler pulley may damage the tensioner. Check the movement of the tensioner arm with the engine off.

Is tensioner pulley necessary?

When Installing A New Belt, Don’t Forget Tensioners And Pulleys. Automatic belt tensioners play an essential role in the accessory-drive system. … A damper inside the tensioner provides the correct amount of belt tension, absorbs vibrations from the engine and reduces noise from a slipping or worn belt.

How long does it take to replace a pulley bearing?

Replacing the pulley should only take an hour or two, and the parts will vary in cost from one type of car to the next.

How do you release a tensioner?

To loosen an AI tensioner, such as an alternator, loosen the main mounting bolt, usually on the engine, and the locking bolt, usually on a bracket or arm. If equipped with a tensioner screw, back off the tensioner screw. Then, push the alternator toward the other pulleys, loosening the belt.

What size socket do you need for a tensioner pulley?

Inspect the belt tensioner pulley to see what size gap it has for a tool to fit in. If the gap is 1/2 wide and square, as is the case in many vehicles, a standard 1/2 inch ratchet will be sufficient.