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Symptoms of a Bad or Failing AC Compressor Belt

compressor belt

The AC compressor belt is a very simple component that plays a very important part in the AC system. It simply connects the compressor to the engine, allowing the compressor to be turned with the engine’s power. Without the belt, the AC compressor cannot turn and will be unable to pressurize the AC system.

With time and use, the belt will begin to eventually wear and will need to be replaced, as the belt is made of rubber. A simple visual inspection searching for a few cues to the belt’s overall condition will go a long way in keeping the belt and the entire AC system functioning properly.

1. Random cracking in the ribs of the belt

When examining the condition of the AC belt, or any belt for that matter, it is important to check the condition of the ribs. The ribs (or rib if it is a V-belt) ride on the pulley’s surface and provide the grip so that the belt can turn the compressor. Over time, with exposure to the heat of the engine, the rubber from the belt may begin to dry out and develop cracks. Cracks will weaken the belt and leave it more susceptible to breaking.

2. Chunks of the belt missing

If when you examine the belt you notice any chunks or pieces missing from the belt, then the belt is probably severely worn and needs to be replaced. As the belt ages and wears, chunks or pieces may break off from the belt as a result of multiple cracks forming near each other. When pieces begin to break off that is a sure sign that the belt is weakened and needs to be replaced.

3. Abrasions on the back or sides of the belt

If when examining the belt you notice any abrasions along the tops or sides of the belt, such as tears or loose hanging threads from the belt, then this is a sign that the belt has received damage in some way. Tears or abrasions along the sides of the belt may indicate damage from not riding the grooves of the pulley properly, while tears along the top may hint that the belt may have made contact with a foreign object such as a rock or bolt.

If you suspect that your AC belt may need replacing, have it first inspected by a professional technician, such as one from YourMechanic. They will be able to go over the symptoms and replace your AC belt if necessary.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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