Genuine Audi Clutch Master Cylinder

Audi Clutch Master Cylinder Parts and Q&A

• Master Cylinder
  8E1-721-401-AJ
  Q: How to remove and install the components related to the Clutch Master Cylinder on Audi A4?

  A:

  In order to take the parts off, one must first of all detach the connection of the cable to the negative terminal of the battery. Then, undo the cowl cover and electronic box containing PCM and auxiliary relay center in order to expose hydraulic lines. To prevent the possibility of spilling brake fluid, put rags under the clutch pedal to soak up any spills, so that brake fluid does not get into the plenum chamber and touch the transmission; in this case, clean the area completely. In the cowl chamber, remove the fluid supply hose between the clutch master cylinder and jam the line. Disconnect the pressure line plug of the clutch master cylinder and pull off the clip and plug out the line to avoid fluid leakage and contamination. Take away the brake master cylinder reservoir retaining bolt and electrical connector to the fluid level sensor to be able to tilt the reservoir on its axis to reach the upper brake master cylinder/booster mounting bolt. Unattach the two long bolts that hold the brake master cylinder/booster to the pedal assembly bracket. Removal of the left side under-dash panel, removal of the clutch pedal and over center spring take place inside the vehicle. Unscrew the brake pedal off of the booster, take the pinch bolt that attaches the steering column shaft universal to the steering gear input shaft off, and detach the universal joint of the steering gear input shaft. Dislodge the electrical connector to the switch of clutch pedal, brake light switch, and accelerator pedal module. Unscrew the upper mounting fastener of the pedal assembly and drop the pedal assembly. Clamp is released by pushing down on the sides of the holding clip without letting the clutch pedal be free and trying to break the clutch pedal switch. Disengage the pin holding the clutch master cylinder to the clutch pedal, push the pushrod pin out and take off the clutch pedal. Unscrew the mounting bolts, unscrew the master cylinder of the pedal assembly, be careful not to pour fluid on the carpet. To install, undo all the steps of removal, verify that all the fasteners are tightened to the appropriate torque amounts, bleed the clutch hydraulic system and verify that the brake fluid is at the right level in the reservoir by adding fluid to the reservoir as needed.
• Master Cylinder
  4A1-721-401
  Q: How to remove and install the Clutch Master Cylinder on Audi A6?

  A:

  Remove the plenum chamber cover, switch the ignition OFF, and disconnect the battery ground strap. Clamp the supply hose from the brake fluid reservoir using a special pinch tool, then pull the hose off the master cylinder and plug it. Remove the supply hose grommet from the bulkhead, lever out the retaining clip using a screwdriver, and pull the pipe out slightly. If equipped, remove the bolt and swing the brake fluid container to the right. Remove the Torx bolts, then working under the dashboard, remove the driver's storage compartment. Detach the clutch pedal from the master cylinder by unclipping the pin and carefully pressing the clutch pedal off. Remove the bolts for the clutch master cylinder and the mounting bracket, then pull the complete pedal assembly slightly to the rear and remove the clutch master cylinder. To install, insert the clutch master cylinder and tighten the bolts, ensuring the seal with the washer contacts the mounting bracket at the rear. Press the connecting pipe into the recess at the mounting bracket, slide the complete pedal assembly forward, insert the bolt, and tighten by hand while having an assistant guide the pipe from the plenum chamber into the clutch master cylinder. Tighten the mounting bolts for the brake booster and the mounting bolt for the brake fluid container. Press in the retaining clip, push the pipe into the clutch master cylinder until it engages audibly, insert the supply hose rubber grommet into place on the bulkhead, and push in the supply hose from the brake fluid reservoir. Remove the special tool, tighten the pedal assembly bolt to secure it to the dashboard carrier, connect the clutch master cylinder to the clutch pedal, and engage the bolt lock in the clutch pedal. Bleed the clutch system after installing the clutch master cylinder, check the adjustment of the vent valve above the clutch pedal, ensuring it contacts the clutch pedal completely and operates at full travel. The gap measurement between the retaining clip and the mounting bracket may be a maximum of 0.5 mm, and to adjust, hold the clamp and turn the vent valve. Finally, install the driver's storage compartment.