The Honda Civic serpentine belt controls a variety of components in a vehicle's engine, starting with the crankshaft, then the alternator, the water pump, air conditioner pump and power steering. When the engine is running the crankshaft pulley turns and the serpentine belt drives the other components. But when the belt becomes old, it begins to fray and stretch and needs to be replaced. The belt is kept tight with the automatic belt tensioner, which you can manoeuvre to work on the belt.
Park the Honda Civic in a flat place and set the parking break. Lift the bonnet.
Use the adjustable wrench to disconnect the leads on the battery so you can work on the engine without fear of any electrical problems occurring.
Locate the serpentine belt configuration chart on the shroud cover of the radiator fan. This lets you see how the belt is routed through the various components of the engine. It varies depending on what model of Civic you own. Refer to this diagram for proper routing of the belt after adjustments are made.
Stand in front of the vehicle and locate the belt tensioner on the left-hand side of the alternator. Find the bolt that protrudes from the belt tensioner. Match an appropriate-sized socket to the bolt head.
Attach the socket to the breaker bar ratchet. Slot the socket over the end of the bolt. Apply leverage in the direction indicated on the belt routing diagram to loosen the tensioner pulley and adjust the tension on the belt.
Remove the belt from the pulley with the flathead screwdriver, then slide it off the other pulleys in the system. Release the pressure on the tensioner slowly to avoid injury.
Route the new belt through the pulleys in the Honda Civic. Start with the crankshaft pulley and work your way through the other pulleys in the engine. Refer to the belt configuration chart for proper routing.
Ensure that the grooves on the inside of the new belt match up with the grooves on the pulley. Place a small piece of masking tape on each pulley to keep the belt in place while you work your way through. Leave the tensioner pulley for last.
Apply pressure with the breaker bar ratchet to the automatic belt tensioner for several seconds until it releases the tension.
Slide the new belt in place with the flathead screwdriver and slowly release the pressure on the tensioner pulley until it tightens the serpentine belt.
Remove the pieces of tape, reconnect the battery, and start the vehicle. Run the engine for several minutes to let the automatic belt tensioner adjust the serpentine belt.
Like most other vehicles, the Honda Civic relies upon an automatic belt tensioner to keep the pulley tight. Depending on the type of Civic, there are different pulleys in the system that will be routed through the serpentine belt system. If your configuration chart is missing from your Honda Civic, contact your local Honda dealer for a new Owner's Manual or download one directly from the company website.