Alternator Belt

This procedure covers replacement of the serpentine drive belt (alternator belt) on the 2016-2021 Honda Civic 1.5L Turbo engine, including belt tensioner adjustment and routing verification.

Warnings

Tools required

Parts

• Serpentine drive belt × 1 — Use OEM Honda belt or Gates K060975

Preparation

1. Park vehicle on level ground and engage parking brake
2. Allow engine to cool completely (minimum 30 minutes after running)
3. Photograph or sketch the serpentine belt routing before removal for reference
4. Ensure adequate lighting and access from above the engine bay

Procedure

1. 1

   Access the serpentine belt
   Open the hood and locate the serpentine belt on the front of the engine. The belt drives the alternator, A/C compressor, and water pump. Identify the automatic belt tensioner located on the upper right side of the engine block.
2. 2

   Document belt routing
   Take a clear photograph of the belt routing path around all pulleys. The belt should route around the crankshaft pulley (bottom), A/C compressor pulley (lower right), alternator pulley (right), water pump pulley (upper left), and tensioner pulley (upper right). If a routing diagram is present on the radiator support, verify it matches the current installation.
3. 3

   Relieve belt tension
   Using a 14mm socket or 3/8 inch breaker bar, insert the tool into the square hole on the belt tensioner arm. Rotate the tensioner clockwise (toward the front of the vehicle) to relieve tension on the belt. The tensioner will move approximately 45-60 degrees.
4. 4

   Remove the old belt
   While holding the tensioner in the released position, slip the serpentine belt off the alternator pulley first, then carefully release tensioner pressure. Remove the belt from the remaining pulleys by working it off the crankshaft pulley last. Remove the belt from the engine compartment.
5. 5

   Inspect pulleys and tensioner
   Inspect all pulley surfaces for wear, damage, or contamination from oil or coolant. Spin each pulley by hand to check for roughness or bearing noise. Check the tensioner for smooth operation and verify the tensioner pointer is within the operational range marks on the tensioner body. Replace tensioner if pointer is outside acceptable range or if roughness is detected.
6. 6

   Route the new belt
   Starting with the belt around the crankshaft pulley at the bottom, route the new serpentine belt around all pulleys EXCEPT the alternator pulley, following your reference photo. The typical routing is: crankshaft (bottom) → A/C compressor (lower right) → water pump (upper left) → tensioner pulley (upper right). Leave the alternator pulley for last.
7. 7

   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 while maintaining tension on the tensioner. Carefully release the tensioner to apply proper tension to the belt. Verify the belt is centered on all pulley grooves and fully seated in all V-grooves.
8. 8

   Verify belt installation
   Double-check that the belt is properly seated in all pulley grooves with no misalignment. Compare the installation to your reference photo to confirm correct routing. The ribbed side of the belt should contact all pulleys. Verify the tensioner pointer is within the normal operating range indicators on the tensioner body.
9. 9

   Test belt operation
   Manually rotate the crankshaft pulley clockwise (viewed from front) by hand approximately two full revolutions. Observe that the belt tracks properly on all pulleys without slipping off or misaligning. Listen and feel for any binding or unusual resistance. Re-check that belt remains properly seated after rotation.

Reassembly

1. No disassembly was required for this procedure, so no reassembly steps are necessary
2. Ensure all tools are removed from the engine compartment before starting the engine

Verification

• Start the engine and observe belt operation for 30 seconds, listening for squealing or chirping noises that indicate improper tension or alignment
• Verify the alternator is charging by checking that the battery warning light extinguishes after engine start
• With engine running, turn on electrical loads (headlights, A/C, rear defroster) and verify no belt slippage occurs
• Visually inspect belt tracking on all pulleys while engine is running to confirm proper alignment
• After initial test run, shut off engine and re-inspect belt seating on all pulleys to ensure it has not walked off center

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