Brake Fluid Flush

Because brake fluid absorbs moisture, you need to change your brake fluid about every 1-2 years. Depending on the brand of brake fluid you use, you may need to change the fluid more often. There are several different methods to bleeding your brakes. Each has its own advantages and disadvantages.

1. Hold the brake pedal while loosening the brake bleeder screw allowing fluid to be discharged, then close the screw, let off the brake and repeat the process.

2. Use a type of vacuum device that inserts into the bleeder screw, loosen the bleeder screw and vacuum the fluid through the system.

3. Use some type of pressure unit that clamps onto the master cylinder and applies pressure to the system, loosen the bleeder screws and close off when done.

4. Use a one way check valve inside the bleeder screw that replaces the bleed valves, called a speed bleeder. Loosen the speed bleeder screw and step on the pedal, fluid will come out but the check ball will keep air from entering back into the system when letting off the pedal.

The different methods are all similar in that you will need to open the bleeder screw to allow the fluid to be released.

How I Flush my brakes
I like using the vacuum method because you never touch the brake pedal and it does not require an assistant. It involves a pump that creates a vacuum and a jar that has two ports on it, one to apply a vacuum to and the other to connect to the bleeder valve.

1. First I use a syringe to remove as much brake fluid from the master cylinder as I can. Then top it off with the new fluid. I use ATE super blue racing fluid which comes in Gold or Blue. So I alternate the color to make it easy to see when the old fluid is out and the new fluid is in.

2. If you are in a hurry, for the rears you could back up on ramps, this should give you room to get to the brake bleed valves. The front wheels you could just turn the tires to gain access. OR if you want you can just remove the wheels. This would be a good time to inspect the pads and rotors.
NOTE:You start at the farthest wheel from the master cylinder, the right rear. Don't ask me why…

3. Connect a hose from the jar to the bleeder valve and using the hand pump create a vacuum in the jar. Open the bleeder valve and the vacuum will draw the old brake fluid into the jar. You will see a lot of bubbles in the line. This is not air that is in your system but instead this is air that is leaking past the threads on the bleeder valve. You will notice that by turning the bleeder screw you can change how fast the fluid comes out. I guess it has something to do with how the holes line up between the caliper and the screw. You should see a color change in the fluid letting you know that the line has been flushed.

Flushing the rear, notice the clear brake fluid.

The fluid is blue showing that we have flushed the line.

Flushing the front, notice the clear brake fluid.

The fluid is blue showing that we have flushed the line.

Remember to keep an eye on the master cylinder fluid level. This is the longest line plus what is in the master cylinder so this one will take the longest and require the most fluid.

Make sure you tighten the bleeder valve and put the rubber protective cap back on the bleeder.

Repeat this for the remaining wheels. Don't forget to keep topping off the master cylinder.

Be careful pouring the brake fluid in the master cylinder. If you spill any fluid wipe it up immediately and move the rag away from the car. Brake fluid will dissolve the paint.

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