Steps to Replace Serpentine Belt

• 1). Study the old belt's routing. If the belt is still in place, this shouldn't be difficult, but if the belt is clumped up, a belt-routing placard should be available under the hood depicting the routing, or the owner's manual usually has a routing diagram. If need be, sketch the correct routing before removing the belt.
  
  
• 2). Use a ratchet to loosen the belt, and unthread it from the pulleys (many vehicles have a common 3/8-inch-square hole in the belt tensioner's arm to release the tensioner). Inspect the belt for damage. A very old belt can show cracks, and disintegrating belt edges can show problems with the pulleys, idlers or tensioners. If necessary, realign any bent accessory-mounting brackets, which can make pulleys crooked. You can bend it back in place or use a couple shim washers to do the job.
  
  
• 3). Check the tensioner, as the pulley should run smoothly. An appropriate amount of tension and no friction in the pivot is the goal. Once you install the new belt, you can use a belt tension gauge to check this.
  
  
• 4). Check to see if the area of the belt is oily, as engine oil can quickly ruin the belt's rubber. Clean up any oil and repair any leaky engine seals or gaskets. Also, check the pulley grooves for old rubber or dirt, which you can clean out with a wire brush or brake cleaner.
  
  
• 5). Hold the tensioner slack with one hand while threading the last pulley while installing a new tensioner and belt. Install the belt around the crankshaft pulley and work counterclockwise. However, make sure you keep a little tension on the belt, or else it will slide off.
  
  
• 6). Atart the engine and let it run for a couple minutes after you install the belt. Observe the tensioner arm. The mark on the tensioner body should be between the high and low marks if the belt is installed the right way. Also, reinstall any radiator shrouder you removed to initially access the belt.