How to Bleed a Slave Cylinder

The clutch slave cylinder in your car works much the same way a clutch cable does in other cars. It is used to engage the clutch release mechanism when your vehicle shifts gears. If you ever need to replace the slave cylinder, or if it is creating too much pressure, you will need to bleed the cylinder. You can bleed the cylinder to drain old or contaminated brake fluid in the cylinder. Bleeding a clutch slave cylinder is a very easy DIY task, and this easy to follow step by step guide will show you how to it.

Step 1 - Prepare the Vehicle

Park the vehicle on flat, level ground. Then, disconnect the negative battery cable from the terminal post on your car battery.

Step 2 - Raise and Secure the Vehicle

Raise the vehicle using the floor jack, and then place the vehicle on jack stands.

Step 3 - Remove the Hydraulic Line

Place the plastic drip pan underneath the slave cylinder. Open bleeder and allow any air to escape.

Step 4 - Drain the Clutch Slave Cylinder

Allow brake fluid in the slave cylinder to drain into the drip pan.

Step 5 - Fill the Slave Cylinder with Brake Fluid

Remove the fill plug cap fill the master cylinder with brake fluid until it reaches the fill line level.

Step 6 - Perform Initial Bleed

Use a screwdriver or a wrench to loosen the slave cylinder bleeder valve. Do not open it completely, but rather, turn it only until fluid starts to leak out and you hear air escape from the cylinder. Then, close the bleeder valve.

Step 7 - Refill the Slave Cylinder

Refill the master cylinder with fluid to replace any fluid that escaped during the initial bleed.

Step 8 - Repeat Cylinder Bleeding Process

Remove the valve again and bleed the cylinder. However, this time, have your assistant push down on the clutch pedal until it reaches the floor and ask him/her to hold it there. While the pedal is pressed to the floor, close the bleeder valve. Then, instruct your assistant to pump the pedal a few times and then release it.

Step 9 - Top-Off Cylinder with Fluid

Once again, fill the master cylinder with brake fluid.

Step 10 - Final Bleed

Open the bleeder valve again, and have your assistant again push the clutch pedal all the way to the floor and hold it. However, have the helper hold the pedal only, rather than pump it. Close the valve while the pedal is on the floor.

Step 11 - Final Fluid Top-Off

Top-off the master cylinder for the final time.

Step 12 - Finishing Up

Lower the vehicle, reconnect the negative battery cable and take your car for a test drive to ensure the clutch works properly.