If you notice your clutch has been feeling “spongy” or doesn’t want to fully engage or disengage, you should probably change your hydraulic clutch fluid. Luckily, the process is relatively easy and should take only an hour to complete. Just what you need is the tools and a friend, and then follows the directions stated below.
1 – FIND THE BLEEDER VALVE AND ATTACH TUBING
First, confirm from your owner’s manual to find the location of the bleeder valve on your clutch system. It’s mostly found near the bottom of the clutch slave cylinder, on or near a hydraulic line leading to the cylinder. Once you’ve found the valve, fit the clear, plastic tubing around the valve, and run it into the clean container you want to use. You can use whatever container you have available, like an old milk jug.
2 – INSPECT THE FLUID LEVEL
Next, you should inspect the level of the fluid in the reserve thank. Again, confirm from your manual for its exact location, but you can often find it close to the rear of the engine compartment on the driver’s side.
Increase fluid to the full level. You will likely want either DOT-3 or DOT-4 fluid, though you should use the type your manual recommends. It’s important that the reservoir never empties completely during the fluid flush or replacement process, as this will let air into the hydraulic system, almost reducing its effectiveness.
3 – PUMP AND DEPRESS THE CLUTCH
Have someone pump the clutch pedal gently a couple of times, and then press the pedal all the way to the floor and hold it. It is important that the pedal stay on the floor until the next step is finished.
4 – OPEN AND CLOSE THE BLEEDER VALVE
Gently turn the bleeder screw with a wrench until you notice fluid moving down the tubing you’ve attached to the bleeder valve. Your wrench should likely be 8 mm, but you should check your owner’s manual for your brand specifics.
Let the valve open until you see the flow slow, then close it fully again. Do not over-tighten it since it will have to be loosened again. However, ensure it’s fully closed, as failing to do so can let air into the system.
5 – RELEASE THE CLUTCH PEDAL AND ADD FLUID IF REQUIRED
Once you have re-closed the bleeder valve, have someone release the clutch pedal. The pedal may not rise on its own, so someone may have to pull it up with his toe or hand.
Then, check the fluid level in the reservoir tank, and add fluid if it has drained more than halfway. If in doubt, add more fluid.
6 – REPEAT STEPS 2-5 UNTIL FLUID IS CLEAN
Lastly, repeat steps 2-5 until the fluid coming through the tube is clean. Watch the color and consistency of the fluid coming out through the bleeder valve. The old fluid will have a visibly brownish tint, and it may have dirt’s in it. When the fluid coming out of the valve through your plastic tube becomes clear, you may stop. If the fluid is clear, but you’re still seeing small debris in it, keep flushing it until it is gone. You may use up to two bottles of brake fluid.
7 – CLOSE THE BLEEDER SCREW
Next, close the bleeder screw as firmly as you can without over-tightening it with the wrench. You don’t want any leaks, but you also don’t want to strip the screw or the fitting.
8 – TAKE AWAY THE TUBING AND DISPOSE OF BRAKE FLUID
Remove the tubing, and dispose of the old brake fluid. Most auto-parts repairs stores have safe disposal services for used automotive fluids, so you should contact a nearby one.
9 – INSPECT FLUID LEVELS AND TEST DRIVE
Next step, wipe down the bleeder valve area with a dry rag before checking the fluid one last time. Add fluid to fill if needed.
Test the Clutch
Then, place a piece of cardboard underneath the bleeder valve, and test the clutch by slowly pumping it a few times with the engine running. If there’s no fluid on the cardboard, you can take the car out to be sure the clutch is functioning normally.