How to Bench Bleed a Master Cylinder in Vehicles

by Contributing Writer; Updated June 12, 2017

The Vehicles is a versatile car and the most popular Vehicles model sold in the U. S. When replacing the brake master cylinder in a Vehicles you should bench bleed the new one before installing it to ensure there isn't any air in the system that can get into the brake lines.

Under The Hood:

 How to Bench Bleed a Master Cylinder in a VW Jetta

Remove your old master cylinder before you bench bleed and install the new one. The brake master cylinder of a VW Jetta is generally located up against the driver's side firewall, behind the tube coming from the air filter. You may need to remove the top of the air filter as well as the tube to remove and install the master cylinder.

Set your new VW Jetta master cylinder in a bench vise; if you don't have a bench vise, you can use a clamp-on vise and an old table. Clamp the cylinder firmly into place, making sure that it's level. Open up the bench bleed kit and have it close by.

Put the old reservoir into the new master cylinder, if you're reusing it. Be sure you dry off the reservoir completely, since brake fluid absorbs water and can damage your brake system, and then install it into the top of the new master cylinder. If a reservoir came with your new VW Jetta master cylinder, you can skip this step.

Find the two fittings that came with your bleeder kit. Thread them onto the outlets located on the side of the cylinder. Take the two lengths of hose that came with your kit and insert them into the fittings. Bend the hoses up, so they're aimed into the fluid reservoir.

Cut the hoses, if necessary, so they stick point-down into the reservoir and extend about halfway into it. Use a clip to secure the tubes to the side of the reservoir and keep them in place. You don't want them to come loose and allow air into the system or spray brake fluid around.

Fill the VW Jetta's reservoir with fresh brake fluid. Pour enough into the reservoir to fill it just shy of the maximum fill line. The plastic hoses will extend down into the fluid, creating a closed hydraulic system.

Pump the piston on the brake master cylinder to move the fluid through the unit and into the hoses. Use a Phillips screwdriver to do this by putting it into the cylinder and pushing it firmly against the piston to start pumping.

Watch for air bubbles coming out of the hoses and into the fluid in the reservoir. Keep pumping until all the air is out of the cylinder and you don't see any more bubbles. Consider buying clear hoses if the ones that come with your kit are black, so you can see the air bubbles better.

Leave the two hoses in the reservoir and slowly remove the cylinder from the vise. You can now install the primed master cylinder into your VW Jetta.

Items you will need

  • Replacement master cylinder (varies by model year and engine type)

  • Bench bleed kit (may come with the cylinder)

  • Bench vise or clamp-on vise

  • Bottle of DOT 3 brake fluid

  • Phillips head screwdriver

 How to Bench Bleed a Master Cylinder in a Chevy Silverado

Remove the old master cylinder before you bench bleed the new one. It sits prominently on the driver's side of the engine compartment to the right of the engine. You can clean and reuse the old reservoir or get a new one (some master cylinders come with one).

Set the new Chevy Silverado master cylinder in a vise on your work bench or table. Clamp it into place, ensuring that it's level; this helps make sure air pockets don't form during the process. Remove the supplies that came in your bleeder kit and set them out, so you can inventory what you have.

Install the reservoir onto the replacement cylinder, if it's not already done. Find the two fittings that came with your kit and screw them into the outlets on the side of the cylinder. Insert the two lengths of plastic tubing from the kit into the fittings, then bend them up so they aim into the brake fluid reservoir.

Cut the hoses so they stick halfway down into the reservoir. Clip the two tubes to the lip of the reservoir to keep them in place, so you don't end up allowing air into the system or spraying brake fluid everywhere.

Fill the Chevy Silverado's reservoir with fresh brake fluid. Put enough fluid into the reservoir to fill it just short of the maximum fill line. The hoses should extend down into the fluid to make a temporary hydraulic system.

Pump the piston on the master cylinder to push the brake fluid through it and into the hoses. Do this by inserting the screwdriver into the cylinder and pushing it against the piston to start pumping the fluid. The fluid will recycle back into the reservoir, but that's okay since you used fresh fluid.

Watch for the air bubbles coming out of the hoses and into the brake fluid in the reservoir. Keep pumping until all the air is out of the cylinder and bubbles no longer appear. If the hoses that came with your kit are black, you might want to buy clear ones to help you see the bubbles better.

Keep the hoses in the reservoir and remove the cylinder from the vise. Now you can install the primed master cylinder into your Chevy Silverado.

Items you will need

  • Replacement brake master cylinder (varies by model year and engine type)

  • Bench bleed kit (may come with the cylinder)

  • Bench vise or clamp-on vise

  • Bottle of DOT 3 brake fluid

  • Phillips head screwdriver

 How to Bench Bleed a Master Cylinder in a Ford Taurus

Remove the old brake master cylinder from your Ford Taurus. Look for it up toward the firewall, behind the air box tube and next to the strut tower.

Put your new brake master cylinder in a bench vise or clamp it to an old table to keep it in place. Make sure it's level when you tighten the vise.

Look for the two fittings that came with your bleed kit and screw them into the outlet holes on the side of the Ford Taurus's master cylinder; they may both be on one side or there could be one on each side, depending on which model year you own. Locate the two pieces of tubing in the kit and insert them snugly into the fittings.

Bend the tubes up and insert them into the reservoir. Cut them, if you need to, so they sit with the ends about halfway into the reservoir. Clip them to the lip of the reservoir, so they stay put and don't slip; you could end up with air in the system and have to start over, if you skip this.

Pour fresh DOT 3 brake fluid into the reservoir. The hoses will extend down into the fluid, creating a hydraulic system. This means you won't have to clamp the tubes to avoid letting fluid flow back into the master cylinder while you work.

Insert your screwdriver into the Ford Taurus's brake master cylinder and push. This moves the piston, forcing brake fluid into the cylinder to clear the air out of it. You'll see brake fluid recycling back into the reservoir, which doesn't pose a risk since you used fresh fluid.

Watch for air bubbles coming out of the tubes. If you have clear hoses, you'll see the air bubbles moving through the tubes; if your tubes aren't transparent, watch for bubbles coming out into the fluid in the reservoir. Sometimes bleed kits come with black tubes, so consider buying clear ones, if this is the case.

Keep pumping the piston steadily until you no longer see air bubbles. Leave the hoses in the master cylinder, carefully remove it from the vise and install the primed cylinder in your Ford Taurus.

Items you will need

  • Replacement brake master cylinder (varies between model years)

  • Bench bleed kit (may come with the cylinder)

  • Bench vise or clamp-on vise

  • Bottle of DOT 3 brake fluid

  • Phillips screwdriver