Z31 Clutch System Issues

So you go to start your Z on a cold winter morning and when you push your clutch pedal down it sticks on the floor. What causes this you may ask. This is caused by a lack of fluid in the clutch hydraulic system. Usually this is because of a failed Clutch Master Cylinder or Failed Clutch Slave Cylinder.

Fixing this issue is easy, But you will need to bleed the system and that usually requires 2 people. First thing it so locate where the leak may be. The Clutch master cylinder is located directly next to the Brake system Master cylinder. It is much smaller but functions the same. You will want to look near the firewall for any drips of fluid as well as inside on the drivers foot well as the seals fail, fluid will leak out in either or both locations.

The second location to look is under the car on the right side of the transmission. This is where the Slave cylinder is located. You will see a small rubber boot that may be wet with fluid. If so this is the issue and needs to be replaced.

When ever you see this issue I do Recommend replacing both the Master and Slave cylinders as a pair because when one fails the other is not far away from failing.

One last item when working on the Z31 clutch hydraulic system, Nissan installed a fluid dampener inline with the master and slave.

This was meant to soften the response of the clutch engagement/disengagement to the pedal. You may notice a better feel to your pedal if you Remove the dampener and replace it with a front brake line from a S130(280zx). This way you also do not need to bleed the dampener as well as the slave when making repairs on the clutch hydraulic system.


1982 280Zx front brake line- Replaces the clutch dampener

Bleeding Process


    Items Needed
  • Dot 3 Brake Fluid
  • 10MM Box Wrench or Line Wrench
  • A Friend

    Process
  1. Start by topping off your clutch master cylinder with the DOT 3 brake fluid
  2. Connect a hose to the bleed nipple on the Clutch Dampener( if equipped) and place the end into a container filled with DOT 3 brake fluid.
  3. Have your Friend pump the clutch pedal a few times to build pressure and then hold the pedal down
  4. With the Clutch pushed down and held crack open the bleeder until the pressure is released.
  5. Close bleeder
  6. Repeat until no more bubbles are seen in the fluid.
  7. Once the dampener is bled repeat the process on the slave cylinder

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