Alternator Belt

This procedure covers the removal and replacement of the alternator drive belt (serpentine belt) on the 2015 Kia Forte with 1.8L I4 engine.

Warnings

Tools required

Parts

• Alternator serpentine belt × 1 — Use OEM specification 25212-2E100 or equivalent

Preparation

1. Park vehicle on level surface and engage parking brake
2. Turn off engine and allow to cool completely
3. Open hood and secure with hood prop
4. Take a photo of the belt routing diagram on the radiator support for reference, or photograph the current belt routing before removal

Procedure

1. 1

   Locate belt tensioner and identify routing
   From the front of the engine, locate the automatic belt tensioner on the right side of the engine. Verify the belt routing against the diagram on the radiator support or underhood label. The belt wraps around the crankshaft pulley, alternator, tensioner, A/C compressor, and water pump.
2. 2

   Release belt tension
   Insert a 14mm socket or 3/8" breaker bar into the square or hexagonal hole in the center of the belt tensioner arm. Rotate the tensioner clockwise (toward the passenger side) to release tension on the belt. The tensioner will move approximately 30-40 degrees.
3. 3

   Remove old belt
   While holding tension on the tensioner, slip the belt off the alternator pulley first, then release the tensioner slowly. Remove the belt from the remaining pulleys and extract it from the engine bay. Inspect the belt for cracks, glazing, fraying, or contamination.
4. 4

   Inspect pulleys and tensioner
   With the belt removed, manually spin each pulley to check for roughness, bearing noise, or excessive play. Check the tensioner arm for smooth operation and proper spring tension. The tensioner should return to its rest position and hold firm. Replace any worn components before installing new belt.
5. 5

   Route new belt
   Starting at the crankshaft pulley at the bottom, route the new belt around all pulleys EXCEPT the alternator pulley, following your reference photo or the routing diagram. Ensure the ribbed side of the belt contacts all pulleys and the belt is seated properly in each groove.
6. 6

   Install belt on alternator
   Using the 14mm socket or breaker bar, rotate the tensioner clockwise again to create slack. Route the belt over the alternator pulley, ensuring it seats fully in the pulley grooves. Slowly release the tensioner to apply proper tension to the belt.
7. 7

   Verify belt installation
   Visually inspect all pulleys to confirm the belt is properly seated in all grooves with no twists or misalignment. The belt should run straight and true on each pulley. Manually rotate the crankshaft pulley two complete revolutions clockwise using a socket on the crankshaft bolt to ensure the belt tracks properly and doesn't slip off.

Reassembly

1. No disassembly was required for this procedure
2. Double-check that belt is properly seated on all pulleys before starting engine

Verification

• Start the engine and listen for any squealing, chirping, or unusual noises from the belt area
• Observe the belt while engine is running at idle to ensure it tracks straight on all pulleys without wobbling or slipping
• Turn on electrical loads (headlights, A/C, radio) to verify alternator operates properly under load
• Verify battery charging voltage is between 13.5-14.5 volts with engine running
• Re-check belt routing matches the diagram and all accessories operate normally

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