OEM 2004 Chevrolet Trailblazer Brake Master Cylinder

2004 Chevrolet Trailblazer Parts Questions & Experts Answers

• Q: How to overhaul the brake master cylinder on 2004 Chevrolet Trailblazer?

  A: The Brake Master Cylinder overhaul begins with vehicle removal of the component then mounting it into a bench vise where technicians can access the rear of the primary Piston. Shear the outside surface of the master cylinder reservoir before discarding the cap and diaphragm to check for cracks, cuts and nicks and replace damaged components. Detach the master cylinder reservoir before using a smooth round tool to compress the primary Piston for extraction of the Piston retainer and primary Piston assembly from the cylinder. Connection points of the cylinder inlet ports and rear outlet port shielded from airflow while filtered non-lubricated air at low-pressure is applied through the front outlet port to extract the secondary Piston and both primary and secondary seals plus the return spring. Separate the primary Piston assembly together with Piston retainer and seals along with the seal retainer from the secondary Piston. It's crucial to examine and replace the master cylinder if any of these conditions are present in the clean-up process using denatured alcohol: cracks, scoring, pitting or corrosion inside or outside the master cylinder or secondary Piston or return spring. Apply delco supreme 11 brake fluid with gm p/n 12377967 (Canadian P/N 992667) or an equivalent dot-3 brake fluid from a sealed container to all master cylinder bore areas and secondary Piston components and return spring assembly and overhaul parts. All components must undergo drying and lubrication using non-lubricated filtered air. Dosy the lubricated new primary seal and retainer with the new secondary seal onto the secondary Piston before installing the lubricated return spring along with the secondary Piston assembly into the cylinder bore followed by the lubricated new primary Piston assembly . A smooth round-ended tool should be used for pressing down the primary Piston before installing the new Piston retainer followed by reinstalling the master cylinder reservoir cap with diaphragm and reservoir before reinstalling the master cylinder into the vehicle.