Tools You'll Likely Need:
* Jack and jack stands: Securely lift and support the Blazer.
* Wheel chocks: For added safety.
* Socket wrench set: Various sizes, including metric and SAE.
* Ratchet and extensions: To reach tight spaces.
* Wrench: For holding bolts in place while loosening/tightening.
* New idler pulley: Ensure you get the correct replacement part for your specific Blazer.
* Penetrating oil (PB Blaster or similar): To help loosen rusted bolts.
* Gloves and safety glasses: Protect yourself.
* Torque wrench: To tighten bolts to the manufacturer's specifications.
General Steps (Adapt as needed for your specific Blazer and pulley location):
1. Safety First: Disconnect the negative battery terminal to prevent electrical shorts. Park on a level surface, engage the parking brake, and use wheel chocks.
2. Access the Pulley: Locate the idler pulley you need to replace. This will likely require accessing the serpentine belt system. You may need to remove some components to get better access, such as plastic engine covers or other belts.
3. Remove the Serpentine Belt: There are several ways to do this, depending on your comfort level and tools. You can use a serpentine belt tensioner tool (highly recommended) or a combination of wrenches and careful maneuvering. Consult your repair manual for the correct method. The goal is to release tension on the belt so you can remove it from the idler pulley.
4. Remove the Idler Pulley: Once the belt is off, you'll need to remove the idler pulley. This typically involves removing bolts holding the pulley to its bracket. Apply penetrating oil if the bolts are stuck. Be careful not to drop the bolts into hard-to-reach areas.
5. Installation of the New Idler Pulley: Carefully install the new idler pulley, ensuring it seats correctly. Tighten the mounting bolts to the manufacturer's specified torque (found in your repair manual).
6. Reinstall the Serpentine Belt: Carefully route the serpentine belt back onto all the pulleys, including the new idler pulley. Ensure the belt is properly seated on all pulleys. You may need to re-tension the belt using the tensioner tool or the correct procedure in your repair manual.
7. Reconnect the Battery: Reconnect the negative battery terminal.
8. Test and Check: Start the engine and check for any unusual noises or belt slippage. Visually inspect the belt and pulley for proper operation.
Important Considerations:
* Belt Tension: Incorrect belt tension can lead to premature wear and failure of other components. Use the correct tensioning method and tools.
* Torque Specifications: Tightening bolts to the incorrect torque can damage components. Use a torque wrench and your repair manual for the correct specifications.
* Engine Type: A 4.3L V6 and a 5.7L V8 will have different configurations, requiring different procedures.
* Multiple Idler Pulleys: The Blazer may have more than one idler pulley. Make sure you're replacing the correct one.
This process involves working with moving parts and potentially under pressure. If you're not comfortable performing this repair yourself, it's best to take your Blazer to a qualified mechanic. Improper repair could lead to significant damage or injury. Remember to always refer to your vehicle's repair manual for specific instructions and safety precautions.
