What do you need to change an alternator?

Remove the main power cable from the alternator. The main power cable will be the thick cable attached to the alternator that runs from the battery. Depending on how much space you have in your specific vehicle, you may be able to use a ratchet, but in some, you may only be able to fit an open-ended wrench.

How do you remove a nut from an alternator?

Use a socket or wrench to remove the nut by turning it counterclockwise. After the nut has been removed grasp the main power cable and lift it from the alternator charge terminal. Locate the control and monitoring wiring harness connector. Grasp the dust boot and pull it back enough to access the connector safety clip.

Do you need to remove serpentine belt to change alternator?

As you loosen the bolts, the alternator will slide in the bracket under the tension of the belt. You may not need to remove the serpentine or accessory belt if it’s not damaged.

Where is the alternator located in a car?

Park your vehicle on level ground with the engine off with the emergency brake set. Use basic tools while wearing eye protection and gloves. Locate the alternator under the hood, it will be near the front of the engine either on top or the bottom. If needed raise the vehicle using a floor jack and secure it with jack stands.

What’s the best way to replace an alternator?

If you find any of those issues, you’ll need to replace it. Remove the alternator from the engine bay. With the belt pulled off of the alternator pulley and the wires disconnected, the alternator should come out freely. You may need to wiggle the alternator around some things in order to remove it.

As you loosen the bolts, the alternator will slide in the bracket under the tension of the belt. You may not need to remove the serpentine or accessory belt if it’s not damaged.

How can I tell if my alternator has an auto tensioner?

You can tell if your vehicle uses an auto-tensioner by looking at the alternator mounting bracket: if the bolts can slide from side to side in the bracket, it does not have an auto-tensioner. You will need to slide the belt off the alternator pulley before you release the auto-tensioner.

What can I use to relieve tension on alternator belt?

Relieve tension on the belt with the auto-tensioner (if equipped). Some vehicles use the alternator itself to apply tension to the serpentine or accessory belt, but others use an auto tensioner pulley.

What’s the main power cable for an alternator?

The main power cable will be the thick cable attached to the alternator that runs from the battery. Depending on how much space you have in your specific vehicle, you may be able to use a ratchet, but in some, you may only be able to fit an open-ended wrench. Unscrew the bolt holding it in place and pull it from where it’s connected.

How do I loosen the bolts on my alternator?

Loosen the bolts on the alternator if there is no auto-tensioner. In cars without an auto-tensioner pulley, you can relieve the tension on the belt simply by loosening the two bolts that secure the alternator to the engine. These will often require a 14mm or 1⁄2 inch (1.3 cm) socket, though you may need to try others.

How big of a socket do you need for an alternator?

These will often require a 14mm or 1⁄2 inch (1.3 cm) socket, though you may need to try others. As you loosen the bolts, the alternator will slide in the bracket under the tension of the belt. You may not need to remove the serpentine or accessory belt if it’s not damaged. Inspect the serpentine belt for damage.

What should my alternator voltage be with a fully charged battery?

Place the multimeter probes on the battery terminals. With the car running, you should be seeing somewhere between 13.25 to 15 volts with a fully charged battery. If you are not, and you are only seeing battery standing voltage (around 12.2-12.5) then your alternator is still not properly charging.

Can a manual tensioner be used to replace an alternator?

The belt tensioner will only travel (swing) so far which can make installing the belt difficult. Never pry or force the belt onto the pulley. Vehicles with a manual tensioner or the belt tightens with the alternator, there should about ½ inch of deflection in the belt between the pulleys with the greatest distance between them. 7

How to replace an alternator on a 1995 GMC?

Somewhere on your vehicle there is a tensioner pulley. You’ll need to move it enough to slip the belt off the pulley. Our ’95 GMC has a standard spring-loaded GM tensioner that required us to pull it back with a wrench.

Where does the power cable for an alternator come from?

Where is the insert jack on an alternator?

Insert jack stands beneath the vehicle for safety once it’s jacked up. Remove the main power cable from the alternator. The main power cable will be the thick cable attached to the alternator that runs from the battery.

Can a car be moved if the alternator is cracked?

On most cars it should not be possible to move the car more than 13mm. Adjust it if necessary by means of the adjustment strap on the alternator. If it is cracked or perishing, replace it.

How do you connect battery cable to alternator?

Connect B+ battery cable to alternator. Turn on battery switch. Install a jumper from pin F in harness plug to B+ terminal on alternator. Note: the alternator charge wire routes direct to the battery and not through any switch connection, the alternator will not operate correctly if not connected direct to battery or directly through the ammeter.

How do you get an alternator back in place?

You might have to wiggle the alternator around to squeeze it back into place in a crowded engine bay. Be sure to hold loose wires or the serpentine belt out of the way as you get it into place. Be careful not to trap any wiring behind the alternator as you slide it into place.

What causes an alternator to go over base voltage?

If you are getting more than 2 volts above base voltage, most likely your alternator is over-charging the battery or the battery is faulty. Other potential problems are a faulty voltage regulator or a problem in the charging system wiring.

What should the voltage be on a GM alternator?

GM typically runs a fusible link wire between them for overload protection and they can go bad, mimicking a bad alternator. A voltage drop of .25 volts or less is Ok and the alternator is bad. A voltage drop of .5 volts or more means the wire is bad.

Is the alternator the only thing that powers the car?

Many people assume that the car’s battery is the only thing that powers all electrical components in the car. But, this is not true. The alternator plays a vital role in supplying power to the car’s AC, recharging the battery and ignition.

How do you change the alternator on a car?

Changing the alternator on most cars is generally the same. Find the alternator (has to be connected to the serpentine belt), and then look up steps to replace it. The main difference in cars is where the alternator is and how it’s mounted.

Can a bad car battery cause an alternator to not charge?

In theory a car can run only with the alternator charge, but this can cause heavy voltage spikes and other strange symptoms so this means that a bad car battery can cause an alternator to not charge also. Cars are increasingly coming with modern electronics.

What do you need to change an alternator?