This information is drawn from the Max Ellery Book for the Hilux/4-Runner from 1970 to 1997.
1. Verify that the brake fluid level is within the ranges indicated on the cylinder reservoir.
2. Add the appropriate amount of brake fluid.
3. Verify that the reservoir cap’s air vent is free of obstructions and that air can pass through it.
1. Attach a tube to the bleed valve on the slave cylinder and place the other end of the tube in a brake fluid bottle that is halfway filled.
2. With a helper, repeatedly press down on the clutch pedal while the bleed valve is just free enough to let brake fluid (and air, if present) drain out of the hose connected to the bleed valve.
3. Before allowing the clutch to return to its initial position, tighten the bleed valve.
4. Continue carrying out procedures 2 and 3 until the system is devoid of air. This can be determined by feeling the clutch pedal firmly when it is depressed.
5. Check the brake fluid level in the master cylinder reservoir and top it off to the stated levels to prevent air from getting into the system.
6. Top off the master cylinder with the recommended braking fluid; do not use fluid that has been bled from the clutch system.
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How should a clutch be properly bled?
Do the following to bleed your clutch:
- Lift up the car’s front end.
- Detach the hood.
- Remove the reservoir cap from the clutch fluid. Ensure that the reservoir is filled all the way to the top.
- Onto the reservoir’s top, screw the pressure bleeder.
- A couple clutch pumps are needed.
- If utilizing a power bleeder, keep an eye on the gauge and pump the pressure to around 12 PSI.
- Go under the car after grabbing these things:
- pliable tubes
- Cup
- Wrench
- Locate the bleed valve and the clutch slave cylinder. Spray some penetrating oil on it if it has deteriorated.
- Make sure the bleed valve can be turned.
- Prepare the cup to collect fluid, then place the hose over the bleed valve.
- Holding onto the hose, turn the bleeder valve open by roughly a 1/4 turn with the wrench. Begin keeping an eye out for fluid and air bubbles.
- Watch for the bubbles of air to stop. Tighten the valve and take out the tube once they stop.
- Although you shouldn’t have lost much fluid, you should nevertheless fill the reservoir all the way up.
- Check the clutch. It ought to be more constricted and simpler to engage. If the spongy pedal quickly returns, you might require a new clutch slave or master cylinder.
Practically speaking, air in the clutch system typically results in low pedal throws and inefficient gear engage/disengage. There are three ways the driver can handle this scenario.
How is a hydraulic clutch bled?
The following are the fundamental procedures for bleeding clutch fluid:
- First, determine the amount of fluid in your clutch fluid reservoir. With fresh clutch fluid, fill it all the way to the fill line.
- The second step is to locate the bleeder screw and place a pan beneath it.
- Step three is to have your assistant pump the clutch a few times, then fully depress and hold it.
- Step Four: Using your wrench, slightly loosen the bleeder screwabout a half-turn. You ought to notice and hear liquid and air leaving the valve.
- Step 5: Tighten the screw after the bleeding has subsided. Release the clutch pedal after it is completely tightened, then add more clutch fluid.
- Step 6: Continue doing this until the bleeder screw releases only liquid and you are unable to hear or feel air escaping. Retighten the bleeder screw just enough to make it snug without overtightening. A full fluid reservoir should be present.
Your clutch issue should be solved as a result. To be sure your clutch problem is fixed, you might wish to first drive in a parking lot, driveway, or other empty location. To make sure no fluid is escaping when the car is parked, you might want to place a piece of white paper or cardboard underneath it. If it is, all you need to do is tighten the bleeder screw.
It’s crucial to remember that throughout this technique, you shouldn’t entirely drain the clutch of fluid. Instead of draining the clutch, you are bleeding it. The steps will need to be repeated if you totally empty the clutch fluid reservoir because there will likely be more air in it when you refill it.
How can air be removed from a hydraulic system?
You can get rid of dissolved air by increasing the fluid’s temperature until it escapes. Given that hydraulic oil typically contains at least 10% dissolved air, this should only be done in extreme cases.
How can I tell if my clutch needs to be bled?
There are some indicators that a clutch need bleeding. When you see these symptoms, kindly take a break and bleed your car’s clutch.
Spongy or soft clutch pedal
The clutch of an automobile is made to feel smooth and springy when in use. If the clutch in your car seems excessively spongy or mushy when you press the clutch pedal, you may need to bleed the clutch.
Difficulty in clutch release
When activated, the clutch pedal of a car should release easily. The slave cylinder may have air bubbles or the clutch fluid may be low if a car’s clutch won’t release after being engaged. The clutch has to be bled.
Difficulty in gear shifting
Hard gear shifting will occur if the slave cylinder of an automobile cannot be fully moved by hydraulic pressure. Either low braking fluid or air bubbles in the master cylinder reservoir are to blame for this.
It is most likely a hint that clutch bleeding is necessary if it is challenging to move from one gear to the next.
Grinding sound
A gear beginning to grind indicates that the issue has gotten worse. The transmission system may become worn out as a result. In this situation, bleeding the clutch would be necessary to solve the issue. If it still exists, a qualified mechanic should be consulted to investigate.
How can a clutch be bled without a vacuum pump?
Most likely, the clutch system in your car operates similarly to the brake system. In the majority of instances, it might even employ brake fluid as its working fluid. A mechanical clutch, which is what you would have if you drive a vintage automobile or truck, translates the movement of the clutch pedal into movement of the clutch pressure plate, which releases the clutch, using a series of levers, pivot points, and connecting rods. Because hydraulic clutch systems are significantly easier to install, take up less space, and don’t need to be adjusted when your clutch wears out, they are commonly found in new cars.
Before your clutch will function properly, you must do a sufficient job of removing the air from the system, regardless of whether you have replaced the slave or master cylinders of the clutch, the lines, or merely the fluid. This process is known as “Most mechanics recommend bleeding your clutch system because air in a hydraulic system might cause it to malfunction. The master cylinder pushes hydraulic fluidin this case, braking fluiddown the line and into the slave cylinder as you depress the clutch pedal. The slave cylinder will engage as a result of the pressure in this fluid, pressing the clutch fork and disengaging the clutch. The air bubble can collapse if there is air present in the system. The slave cylinder won’t actuate as far or possibly at all since this compressing air bubble will absorb much of the fluid being supplied from the master cylinder to the slave cylinder. It will be challenging to shift your gearbox, especially into first gear from a stop, if the slave cylinder does not travel as far as it should.
You must push or drag the air down through the fluid line to the bleeder valve on the slave cylinder to empty the air out of your clutch system. You should fasten a tube to the nipple on the bleeder valve in order to keep things clean. It may be simple to determine when all the air has left the system if you use a clear tube. Using a vacuum pump to remove fluid and air from the system while keeping the clutch fluid reservoir full is the simplest approach to bleed the clutch. Until there are no longer any visible air bubbles in the fluid, keep pumping fluid from the bleeder valve. If you don’t have a vacuum pump, you and a friend can do this by hand.
Have your friend depress the clutch pedal as far as they can while the bleeder valve is closed. Your companion should keep applying pressure to the clutch pedal as you open the bleeder valve and let the fluid drain until the engine slows down. Close the bleeder valve when the fluid flow slows down while your friend is still applying pressure to the clutch pedal. Repeat the technique by letting the clutch pedal rise once more. Keep doing this until no more air bubbles are visible coming out of the bleeder valve. Your pal ought to feel the pedal “As you go through this procedure, tense up because air compresses more easily than the clutch plate release springs.
Make sure the bleeder valve is completely closed after you’ve finished this step, then take a test drive.
How long does bleed clutch take?
assemble the necessary tools, preferably an 8mm or 10mm line wrench or brake bleeder wrench. The correct type of brake fluid should be DOT (Department of Transportation) 3 or higher; consult the owner’s manual for more information. one to two feet of clear aquarium tubing, Empty the water bottle, drain the pan, Floor jack, companion or assistant (to assist in manual bleeding), Gloves, Vacuum bleeder controlled by hand (Optional), paper towels or rags for cleaning, eye protection, a huge turkey baster, a suction tool, and two safety jack stands
The brake master cylinder is on the driver’s side of the car, close to the firewall. To find it, open the hood and look there.
For normal maintenance, use a turkey baster to remove the old brake fluid from the master cylinder reservoir before replacing it with new fluid. Start by opening the reservoir’s cover.
Fill the clutch master cylinder. To discover the brake fluid specifically for your car, consult your owner’s handbook. Fill the clutch master cylinder with the fluid.
Find the slave cylinder; it will typically be mounted externally on the transmission of most cars. In others, the bleeding valve is accessible from the outside but the slave cylinder is located inside the transmission. Following the hydraulic line from the clutch master cylinder will help you find the slave cylinder the fastest.
Check the location of the bleeding valve or bleed nipple. In rare cases, it may be required to elevate the vehicle off the ground and secure it using safety jack supports in order to access the slave cylinder.
Open the bleeder valve to the slave cylinder by turning the bleeder valve handle with a line wrench. To catch the brake fluid, place a drain pan underneath the slave cylinder.
Bleed the brake fluid by leaving the bleeder open and letting gravity work for one to three minutes to drain the slave cylinder.
Watch the brake fluid level in the master cylinder while gravity bleeding, as a precaution. It’s crucial to keep the brake fluid from getting too low because doing so will result in air being drawn back into the system.
Tip: To release any more air pockets that may be trapped inside the slave cylinder, use your line wrench to tap on it.
Close the bleeder valve on the slave cylinder and attach a section of aquarium tubing to the bleeder nipple to attach tubing to the bleeder nipple. Fill the master cylinder to the top with brake fluid and place the other end in an empty water bottle.
Pump the clutch pedal: If you’re with a friend, ask them to take the wheel and pump the clutch pedal ten to fifteen times to create pressure. Then instruct them to fully depress and hold the clutch pedal.
Test the bleeder – With the clutch pedal firmly down, open the bleeder with your line wrench. Watch the brake fluid and air bubbles coming out of the slave cylinder. Close the bleeder when the flow of brake fluid stops, then ask your assistant to let go of the clutch pedal.
Repeat steps 4 and 5 as necessary until only brake fluid is visible coming from the bleeder on the slave cylinder.
Never let off of the clutch pedal while the bleeder valve is still open. By doing this, air will enter the system.
Advice: It’s normal for the clutch pedal to remain pressed on the floor even after releasing it when bleeding the clutch. Do not panic; instead, pop the wound back up with your foot or by reaching below and let the bleeding continue. The clutch pedal will automatically rise as hydraulic pressure increases and more air is let out.
Never let the fluid level in the clutch master cylinder drop too low while bleeding the slave cylinder; otherwise, air will be sucked into the hydraulic system and the procedure will need to be redone.
Why is my clutch still soft even though it has bled?
which operate hydraulically. They have a durable and long-lasting mechanism that only occasionally needs to be looked at in the fluid.
Check the entire system right away for leaks if the fluid level in the reservoir is more than 6 mm below the top (or the full mark).
Leaks allow air to enter the system, which leads to inconsistent pedal action. Once the issue has been identified and fixed,
The fluid used in braking systems and clutches must both adhere to stringent international standards. It ought to arrive in an airtight, sealed package.
Marks for specifications
Some cars utilize a mineral-based fluid, while the majority use a variety that contains polyalkylene glycol ethers. Check your car’s manual; the two types must never be combined.
Bleed the system once more if the clutch pedal is still mushy after the initial bleeding.
Examine the locations where the pushrods enter the clutch if the pedal is still ineffective.
Fluid is extremely caustic and dangerous. If you get any in your eye, immediately call a doctor and flush it out with fresh water for 15 minutes.
Keep out of children’s reach and be careful not to spill any on your car as it will quickly eat through the paint.