How Do I Get the Air Out of a Hydraulic Clutch Line?

by Contributor

Hydraulic clutches use a hydraulic system to transfer pressure from the peddle to the clutch mechanism. They work in a manner similar to other hydraulic systems like the brakes. When the peddle is depressed, pressure is created at one end of the system and fluid is forced through a tube to a caliber at the other end of the system, which engages the clutch. If air enters the line, when the peddle is depressed the air becomes compressed and no pressure is placed on the caliber. Bleeding the line removes the air bubble and allows the system to function properly.

Park the vehicle on a solid, level surface and turn it off.

Fill the master cylinder to the top with the appropriate hydraulic fluid for the vehicle. The fluid should be new and freshly opened.

Raise the front of the vehicle with the jack and place it on the jack stands. Put the parking brake on and lock the rear wheels.

Remove the dust cap to the bleeder valve and fit the plastic hose to the valve.

Place the other end of the hose in the pail or can.

Open the bleeder valve and allow fluid to slowly drain from the line. Bubbles should be visible in fluid running down the drain line.

After all of the bubbles have left the line, close the bleeder valve.

Refill the master cylinder with new hydraulic fluid.

Open the bleeder valve, then depress the clutch to the floor and immediately close the bleeder valve. This process generally requires two people to preform.

Depress and release the clutch four to five times with a few moments between each cycle. If the clutch sticks (up, down or in between) or offers little to no resistance there are still air bubbles in the line and steps 6-9 need to be repeated.

Remove the drain hose and replace the dust cover. Lower the vehicle off the jack stands.

Tip

  • check Brake fluid is the typical fluid recommended for hydraulic clutches.

Warning

  • close Car maintenance can be dangerous. Always secure vehicles off the ground before working underneath or close to them. Never get into a vehicle on a jack or jack stands.

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