Tools you'll likely need:
* New serpentine belt: Make sure you get the correct size and type for your Blazer's engine. Your local auto parts store can help with this.
* Socket wrench set: You'll need various sizes, probably including metric.
* Ratchet and extensions: To reach hard-to-access bolts.
* Wrench(es): For loosening tensioner pulleys. Often, a 13mm or 15mm wrench will be needed.
* Gloves: To protect your hands.
* Jack and jack stands (recommended): To safely lift the vehicle. Working on the ground is not recommended.
General Steps (These may vary slightly):
1. Safety First: Disconnect the negative battery terminal to prevent electrical shorts. Place the vehicle on a level surface, engage the parking brake, and use jack stands to support it after raising with a jack.
2. Locate the Tensioner: The serpentine belt is kept taut by a tensioner pulley. This pulley will need to be loosened to remove and install the belt. Locate this pulley. It usually has a bolt that needs to be loosened. Some tensioners are spring-loaded, and others use a pivot bolt. Your repair manual will show you exactly where it is and how to loosen it.
3. Loosen the Tensioner: Carefully use the appropriate wrench to loosen the tensioner bolt. This will release the tension on the serpentine belt. You might need to use a combination of leverage and carefully pulling the belt off the pulleys.
4. Remove the Old Belt: Once the tension is released, carefully remove the old serpentine belt from around all the pulleys. It usually snakes around in a specific order. Pay close attention to the routing as you'll need to put the new belt on in the same way.
5. Install the New Belt: Carefully route the new serpentine belt onto all the pulleys in the exact same order as the old belt. Again, your repair manual will have a diagram showing the correct routing.
6. Tighten the Tensioner: Once the new belt is in place, carefully tighten the tensioner bolt. The tension should be firm, but don't overtighten.
7. Check Belt Alignment: Ensure the belt is properly seated on all pulleys and there's no rubbing.
8. Reconnect Battery Terminal: Reattach the negative battery terminal.
9. Start the Engine: Start the engine and check for any squealing or unusual noises. If you hear squealing, you may need to re-check the belt tension or routing.
Important Considerations:
* Consult your repair manual: This is crucial. The diagrams and specific instructions for your year and engine are essential to avoid mistakes.
* Engine size: The process is slightly different between the 4.3L and 5.7L engines.
* Tensioner type: Some tensioners are spring-loaded, others require turning a specific bolt.
* Pulley order: The order of pulleys the belt goes over is crucial. Get it wrong, and the belt might slip or break.
* Belt routing: The path the belt takes around the various pulleys can be tricky. A diagram is essential to get it right.
This is a general overview. Attempting this repair without experience and without referring to a repair manual for your specific vehicle is strongly discouraged. If you're uncomfortable performing this task, take your vehicle to a qualified mechanic.
