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Keep your brakes running smoothly with this easy automotive repair
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Brake fluid is a lubricant that applies pressure to the brake pads to stop your vehicle every time you press down on the pedal. As brake fluid gets older or exposed to air, it absorbs moisture and makes your brakes work less efficiently. If you want to make sure your brakes last and continue working effectively, a simple brake system flush clears out all the old contamination and replaces it with fresh, clean fluid. Flushing brakes is an easy repair that only requires a helper and a few simple tools, so keep reading to learn the signs of bad brake fluid and how to add more to your vehicle.
Steps
Section 1 of 4:
Flushing Your Brake Lines
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Remove old brake fluid from the master cylinder with a baster . Pop open the hood of your vehicle and look for the master cylinder, which looks like a white plastic tank near the back of the engine bay on the driver’s side. Unscrew the cap on the master cylinder. Squeeze the bulb on the baster before sticking the end into the tank. Then, let go of the bulb to suck up the old brake fluid. Squirt the fluid into a large bottle and continue emptying the tank as much as you can. [1] X Research source
- If there’s dirt or dust on the top of the tank, then wipe it off with a clean rag so it doesn’t get into the tank and contaminate the fluid.
- Be careful not to spill any brake fluid onto your vehicle’s paint since it could ruin the color and finish. Lay down a few towels and wipe up any spills right away with soapy water to prevent damage.
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Add fresh brake fluid to the cylinder. Check your vehicle’s manual or the master cylinder’s cap to see if your vehicle requires DOT3 or DOT4 fluid . Stick a funnel into the opening of the cylinder, and pour the fluid up to the max fill line marked on the side of the tank. Wipe the opening off with a clean towel before putting the cap back onto the cylinder. [2] X Research source
- Always use the brake fluid listed for your vehicle to ensure that your brakes run properly.
- Avoid using brake fluid that’s already been opened because it may get contaminated and work improperly. [3] X Research source
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Raise your vehicle on jack stands and remove the tires. Jack your vehicle in the front and position jack stands underneath the frame behind the tires. Lower your vehicle back down so it rests on the stands. Then repeat the process at the back of your vehicle and place jack stands in front of the rear wheels. Once you have the vehicle raised up, remove the lugnuts and tires with a tire iron. [4] X Research source
- While you don’t need to take the tires off of your vehicle to access the brakes, it’s a lot easier to see what you’re doing if you remove them.
- Avoid going underneath your vehicle while it’s still on the jack because it could easily slip off and cause serious injuries. Always place jack stands first.
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Connect a bleed hose to the bleeder valve on your brake. Check your vehicle’s manual to see what order to bleed the brakes, but usually you’ll start with the rear passenger side. Look for the block-shaped caliper attached to the brake. Locate the small rubber cap on top of the caliper and pop it open to expose the bleeder valve. Stick the hose over the end of the bleeder valve, and put the other end into a large empty bottle. [5] X Research source
- Starting in the rear passenger side helps flush the longest brake line first so you’re less likely to have contamination or old fluid left over.
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Press on the brake pedal and open the bleeder valve to flush the fluid. Place a 1 in × 4 in (2.5 cm × 10.2 cm) piece of lumber under the brake pedal to prevent it from being pressed too far. Have a helper press down on the brake pedal until they feel firm pressure. Then, use a box wrench to turn the bleeder valve a quarter turn counter-clockwise. Old brake fluid will start flowing through the hose and into the bottle. [6] X Research source
- Alternatively, use a pressure bleeder kit if you’re flushing the brake fluid on your own. The kit has a pump handle that draws the fluid out when you raise and lower it instead of pressing down on the brake pedal.
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Close the valve and release the pedal when the flow stops. As soon as brake fluid stops flowing out from the valve, use your wrench to tighten it clockwise by a quarter turn. Only have your helper lift off of the brake pedal after you close the valve so air doesn’t get into the brake lines. [7] X Research source
- Air bubbles in the brake lines can cause the fluid to go bad more quickly and make your brakes run poorly.
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Continue opening and closing the valve until the brake fluid runs clear. Press down on the pedal and open the valve again so more brake fluid comes out from the bleeder valve. If the brake fluid runs clear without any contamination, then the line is completely flushed. Usually, you’ll only have to open and close the valve 3–5 times to flush the fluid. Tighten the bleeder valve, detach the hose, and put the rubber cover back over the valve to protect it from dirt and debris. [8] X Research source
- Check the master cylinder every few times you open and close the valve, and refill it with brake fluid if it’s below half. Letting the brake fluid level drop too low can introduce air into the lines and make your brakes work inefficiently.
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Repeat the process on each of your brake lines. Typically, you’ll work from the brakes furthest from the master cylinder to the closest, but check your vehicle’s manual for the specific pattern. Connect to the next bleeder valve and do the same thing as you did on the first brake. Once you finish bleeding the last valve, then you’re finished. Just reattach your tires, lower your vehicle back to the ground, and you’re ready to drive. [9] X Research source
- Take the old brake fluid to a hazardous waste disposal site rather than throwing it in your trash because the chemicals could harm animals or plants in the environment. [10] X Research source If you’re not able to dispose of brake fluid properly, consider having a mechanic flush your brakes instead.
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Tips
- If you don’t feel comfortable flushing your brake system on your own, take your vehicle to a mechanic. Brake fluid flushes usually cost around $100 USD.Thanks
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References
- ↑ https://www.popularmechanics.com/cars/how-to/a1495/how-to-bleed-brakes/
- ↑ https://youtu.be/B24w89F2g_I?t=96
- ↑ https://youtu.be/1O1dOgG9cII?t=674
- ↑ https://youtu.be/t7JCh7PHoDc?t=1637
- ↑ https://youtu.be/ag-Q_lP0dOk?t=271
- ↑ https://www.popularmechanics.com/cars/how-to/a1495/how-to-bleed-brakes/
- ↑ https://youtu.be/B24w89F2g_I?t=180
- ↑ https://www.popularmechanics.com/cars/how-to/a1495/how-to-bleed-brakes/
- ↑ https://youtu.be/ag-Q_lP0dOk?t=174
- ↑ http://www.finishlineusa.com/files/Brake%20Fluid%20Mineral_US%20SDS_English_25%20April%202015.pdf
- ↑ https://www.popularmechanics.com/cars/how-to/a1495/how-to-bleed-brakes/
- ↑ https://youtu.be/t7JCh7PHoDc?t=1523
- ↑ https://www.dubizzle.com/blog/cars/brake-fluid-flush/
- ↑ https://youtu.be/IKo4qVMuDpY?t=30
- ↑ https://www.themechanicdoctor.com/tips-keep-car-mechanically-sound/
- ↑ https://www.themechanicdoctor.com/best-maintenance-tips-new-car-owners/
- ↑ https://www.globalsuzuki.com/after_sales/automobile/pdf/brake_fluid.pdf
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