How to Get Air Out of Brake Lines Without Bleeding

Written by Katherine Duffy and 1 other
Nov 8, 2024

Getting air out of brake lines without bleeding them is a DIY automotive project you can accomplish with a friend and a few household items.

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To get the air out of your vehicle’s brake lines without bleeding, you just need a few household items. This is a car repair job that you can do from home (with the help of a friend).

QUICK LOOK
  • Getting air out of your car’s brake lines without bleeding them is possible with the help of a few household items and an extra pair of hands.
  • Air bubbles in brake lines can reduce your brake system’s efficiency, so removing them is essential for safe driving.
  • Regular brake maintenance is the best way to keep air bubbles from forming in your brake lines.

How to get the air out of brake lines without brake bleeding

Thankfully, you can get the air out of your brake lines without bleeding them—and do this from the comfort of your home!

Tools needed:

  • A plastic hose
  • A glass or plastic canister
  • Shop rags
  • A car jack
  • A funnel
  • Someone to help you

Once you’ve gathered everything you need, follow these step-by-step instructions to remove the air bubbles from your brake lines:

  1. Locate the pressure bleeder: Jack up your car on a safe and level surface. Now, find the bleeder screw and hose underneath your car—the bolt is long, cylindrical, and used to relieve pressure in your brake lines.
  2. Loosen the bleeder screw from the bleeder valve and attach the plastic hose: If you’re using your hands, make sure you have gloves on as brake fluid can be caustic. Once the screw is loosened, place one end of the hose over the bleed screw and the other end into your canister to catch the fluid.
  3. Have someone else apply the brakes a few times: Brake fluid will come out of the plastic hose and into the canister below. Continue this process until all of the fluid is forced out into the container.
  4. Remove hose and clean the screw: Once the fluid has been totally flushed, your friend can stop applying pressure to the brakes, and you can clean the bleeder screw with a shop rag.
  5. Refill your brake lines with old fluid or add fresh brake fluid: If you’re using your old fluid, make sure it settles so no air bubbles remain in the fluid.

To refill your brake lines with fluid:

  1. Unscrew the brake master cylinder reservoir cap.
  2. Using a funnel, slowly pour the brake fluid into the fluid reservoir while keeping the brakes pressed down to create pressure and push out any air bubbles forming.
  3. Be careful not to exceed the maximum brake fluid level.
  4. Tighten the bleeder screw to ensure no air bubbles or leaking occurs after you’ve finished refilling the reservoir.

Repeat this process for each wheel. Once each wheel’s brake line is finished, take your car out for a spin to ensure the spongy, unresponsive feeling from your brakes is gone.

Note: This process is not the same as a gravity bleed, which is great for replacing brake fluid, but not effective at removing air bubbles from brake lines.

Possible causes of air bubbles in your brake lines

Here are the most common reasons why air might have entered your brake lines:

  • Pumping your brakes: This can cause air bubbles to form because it shakes your brake lines around, making air travel through the transport tubes inside each brake line. In certain circumstances, this can lead to trapped air in your brake lines.
  • Brake fluid needs replacing: If you haven’t replaced your vehicle’s brake fluid over your last two brake jobs, your old brake fluid becomes prone to collecting air bubbles. Brake fluid absorbs water over time, which allows air pockets to form when your car sits for extended periods.
  • Improper brake fluid flush: If your last brake fluid flush wasn’t completed properly when new brake fluid was put in your brake lines, air pockets may form in your brake line as the old and new fluid mix.

Why it’s important to remove air from your brake lines

When there’s air in your brake lines, your wind up with spongy brakes, which are less responsive and can be dangerous, especially on busy highways, in congested stop-and-go traffic, or if an animal or object suddenly obstructs the road while you’re driving.

Air bubbles in brake fluid are also abrasive, so they can damage brake system components, like brake calipers and wheel cylinders over time.

If this problem isn’t addressed quickly, your brakes will become progressively worse, making it more and more dangerous to drive. Removing the air from your brake lines will restore proper pressure and responsiveness so you’ll be able to brake quickly when you need to.

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FAQ

  • How long does it take to get air out of your brake lines?
  • Can you prevent air bubbles from forming in your brake lines?
MEET OUR EXPERTS
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Katherine Duffy

Katherine Duffy is an insurance writer who has spent over half a decade in the professional writing industry. Katherine specializes in content geared toward the everyday driver, including advice on insurance companies and coverages, vehicle specs, and car maintenance. As part of her mission to create helpful and relatable articles, she has written over 550 pieces on car insurance and vehicle care. Katherine has also worked as a teaching assistant at Wilfrid Laurier University, where she obtained a degree in English Language and Literature. Katherine is currently pursuing her J.D. at Western Law.

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Melanie Reiff

Melanie Reiff is an expert insurance writer and editor with over half a decade of experience in professional writing. Guided by a lifelong love of storytelling, it’s Melanie’s mission to help people problemsolve by means of creative and engaging content. Melanie specializes in analyzing the ways in which society, technology, and culture intersect, previously working with clients in travel, technology, and social impact to tell their stories.
As an editorial team lead at Jerry, Melanie has translated her prior experience into creating and editing insurance content that can help drivers and homeowners find the solutions they need and make informed moves.
Prior to joining Jerry’s editorial team, Melanie worked as a freelance content marketing strategist and was the full-time director of choir at Rampart High School Acadamy in Colorado Springs.