Genuine Mercury Mariner Brake Booster

Mercury Mariner Brake Booster Parts Questions & Answers

• Booster Assembly - Brake
  9L8Z-2005-A
  Q: How to make operating check, airtightness check, and removal and installation of a power brake booster?

  A: Depress the brake pedal multiple times with the engine off to ensure no change in pedal reserve distance. Start the engine and depress the pedal, noting a slight downward movement if normal. AIRTIGHTNESS CHECK: Start the engine and turn it off after a minute or two. Slowly depress the brake pedal multiple times, observing if the pedal goes down further the first time but gradually rises after subsequent depressions, indicating an airtight booster. Depress the brake pedal while the engine is running and stop the engine with the pedal depressed, checking for no change in pedal reserve travel after holding for 30 seconds, indicating an airtight booster. REMOVAL AND INSTALLATION: Disassembly of the power unit requires special tools and is not recommended for home mechanics. If a problem arises, it is advised to install a new or factory rebuilt unit. In the engine compartment, remove the nuts attaching the master cylinder to the booster and carefully pull the master cylinder forward to clear the mounting studs, being cautious not to damage the Brake Lines. Disconnect the vacuum hose from the power brake booster. In the passenger compartment, detach the pushrod from the top of the brake pedal, ensuring to discard and replace the clevis locking pin on 2008 and later models. Remove the nuts attaching the booster to the firewall. Lift the booster unit away from the firewall and out of the engine compartment. To install the booster, position it correctly and tighten the retaining nuts. Connect the pushrod to the brake pedal. Install the master cylinder and reconnect the vacuum hose. Test the brake operation carefully before normal vehicle use.