Here's a general outline. This is not a substitute for a detailed repair manual specific to your 1984 Caprice. Consult a repair manual (Haynes or Chilton are good options) for precise diagrams, torque specifications, and step-by-step instructions tailored to your vehicle.
Tools You'll Need:
* New Master Cylinder: Ensure you get the correct one for your vehicle.
* Wrench Set: Metric and possibly SAE, depending on your vehicle.
* Socket Set: Metric and possibly SAE.
* Brake Fluid: DOT 3 or DOT 4, as specified for your Caprice. Do not use DOT 5.
* Brake Bleeder Wrench: For the brake bleeder valves on each wheel.
* Clear Tubing: To attach to the bleeder valves during bleeding.
* Container: To catch the old brake fluid.
* C-Clamp (optional but helpful): To compress the master cylinder piston during installation.
* Shop Rags: To clean up spills and keep things clean.
* Gloves: To protect your hands from brake fluid.
* Jack and Jack Stands: To safely lift the vehicle.
* Wheel Chocks: For safety.
Steps (General Outline - Consult your Repair Manual for Specifics):
1. Safety First: Disconnect the negative battery terminal. Raise the vehicle and secure it safely on jack stands. Engage the parking brake.
2. Fluid Drainage: Open the bleeder valves on all four wheels slightly to relieve pressure in the brake system. This will minimize fluid spillage when you remove the master cylinder.
3. Remove the Old Master Cylinder:
* Locate the master cylinder (usually under the hood, near the firewall).
* Disconnect the brake lines from the master cylinder. This is crucial and requires careful attention to avoid spilling brake fluid. Have your container ready to catch the fluid.
* Disconnect the master cylinder pushrod from the brake pedal.
* Remove the mounting bolts holding the master cylinder to the booster.
* Carefully remove the old master cylinder.
4. Install the New Master Cylinder:
* Compare the new master cylinder to the old one to ensure everything aligns correctly.
* Install the new master cylinder, reversing the removal steps. Make sure all connections are secure.
* If using a C-clamp, carefully compress the master cylinder piston. This helps prevent air from entering the system during installation.
5. Bleed the Brakes: This is the most crucial step. Improper bleeding will result in spongy brakes or brake failure. The process usually involves opening each bleeder valve one at a time while having someone pump the brake pedal. Brake fluid should flow out continuously without air bubbles. Consult your repair manual for the correct bleeding order (usually starting with the furthest wheel from the master cylinder). Continue bleeding until all air is removed from the system.
6. Check Fluid Level: After bleeding, check and refill the master cylinder reservoir to the proper level.
7. Test the Brakes: Before driving, carefully test the brakes in a safe area, ensuring they are firm and responsive. If you feel anything unusual, such as spongy brakes or a lack of braking power, recheck the bleeding process.
8. Lower the Vehicle: Carefully lower the vehicle from the jack stands.
Important Considerations:
* Brake fluid is corrosive. Clean up any spills immediately.
* Brake fluid can damage paint. Protect your paint with rags or covers.
* Never work on your brakes if you lack the necessary mechanical skills and knowledge. If unsure, consult a qualified mechanic.
This is a simplified overview. Always consult a repair manual specific to your 1984 Chevy Caprice before attempting this repair. Improperly done, this repair can be extremely dangerous. If you are not comfortable performing this work, take your car to a qualified mechanic.
