Mechanics

FORD TAURUS BUBBLES PROBLEM

2003 Ford Taurus • 200,000 miles

Iust replaced the rear brake shoes on my friends taurus the left brake bled out fine however the right brake will not pressure up it spits fluid and air will but will not push the pads out. I have checked the rear cylinder and it free and clean
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Mercruiserbob
January 6, 2013.




What about the brake hose?
Roy
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Clean and clear

Tiny
Mercruiserbob
Jan 6, 2013.
Keep bleeding it.

Roy

What about the proportioning valve could it be faulty and allowing pressure to return to reservoir

Tiny
Mercruiserbob
Jan 6, 2013.
We have ran a half of a quart thru it all the others bled easily just the right rear spits air and fluid

Tiny
Mercruiserbob
Jan 6, 2013.
If so, then the left front would be doing the same thing

Roy

With no punctuation I can read this three different ways, and you mention rear shoes and pads, but it sounds like you have rear disc brakes and the right piston isn't coming out of the caliper housing. If that is correct, it won't. Chrysler never used that style with the parking brake built into the caliper, and GM went away from that design because it caused so much trouble. The pistons do not self-adjust like you see the front ones do. The pistons only move out when you work the parking brake. Fords are also very well-known to develop rusted parking break cables in as little as a year, so it is common to use a large channel lock pliers to work the two parking brake levers on the calipers. Once the pistons come out and build pressure on the pads, they will continue to self-adjust like normal after that.

Be aware too that if the brake pedal was ever pushed all the way to the floor, due either to pedal-bleeding the system, trying to get the pistons to come out, or when the driver is surprised by a sudden leak, it can easily be damaged. Crud and corrosion build up in the lower halves of the bores where the two pistons don't normally travel. Pressing the pedal over half way runs the lip seals over that crud and can rip them. That may not show up for a few days but it will cause a very low pedal, a slowly sinking pedal, or the inability to build fluid pressure in one or both hydraulic circuits. The clue here is if you can't build pressure to the right rear wheel, you also will not build pressure to the left front wheel. Those two wheels are on the same circuit on "split-diagonal" systems.

If you didn't open the hydraulic system, as in replace any calipers or hoses, you don't need to bleed anything. If you do need to replace the master cylinder, I have a trick that will save a lot of time and the need to bleed at the wheels. It is real effective on Chryslers and any other models that have two steel lines coming out of the master cylinder on the same side. Many Fords have four steel lines, two on each side. That make the trick a little more involved but it can still work. Let me know if it comes to that.

Caradiodoc
Jan 6, 2013.
Hi ASEMaster6371. Sorry for butting into your conversation. Didn't see any replies when I started typing my novel.

Caradiodoc
Jan 6, 2013.
Thanks it appears to be the master cylinder, the front left does the same thing. Thanks for the help

Tiny
Mercruiserbob
Jan 6, 2013.
I think you'll have four lines coming out of the master cylinder so you'll have to adjust this procedure to suit your needs. I don't have enough time left in my life to retype the entire description, so here's a copy and paste version that I gave someone for a Chrysler product: Two nuts hold it to the power booster and two steel lines must be removed by unscrewing two soft brass nuts. To prevent rounding off the soft nuts, use a line wrench, also called a "flare-nut" wrench. It grips the nut on more sides than the regular open end wrench.

Be sure to follow the instructions for bench-bleeding the new master cylinder. Here's a trick that works on Chrysler products to prevent the need to bleed at the wheels. Loosen the two line nuts just a little, THEN unbolt the master cylinder from the power booster. Pay very close attention to the steel lines as you turn the nuts to be sure they're not twisting. If the nuts don't spin freely, the lines will twist and snap off. Then you have another repair to do that involves new fittings and making double flares. Double flares are hard enough for a professional. They're harder to do in the confines of the engine compartment. Pull the master cylinder forward off the mounting bolts, then use it as a handle to twist the two lines upward just enough so those first two inches are not parallel to the ground. Then you can remove the lines. This will prevent the brake fluid from running out of them. Be careful to not drip brake fluid on the car's paint.

After bench bleeding the new master cylinder, leave the reservoir at least half full of fluid. When you install it, you will have to tilt it to line up the ports with the line nuts. Remove one plastic bench-bleeding fitting, then install the steel line nut hand tight. While you do this, fluid will be dripping out, keeping the line and port full. If the nut doesn't thread in easily by hand, it's cross-threaded. Start over and try again until the nut goes in by hand, typically four or five revolutions. If you damage the threads in the aluminum ports, there will be no warranty and you will have to buy another master cylinder.

Once the first line is connected hand tight, do the same thing with the second line. When both fittings are hand tight, twist the master cylinder and lines back down to their normal position, and bolt it to the booster. You'll need a helper for the next step. There will be a little air in the ports and tops of the lines. Tighten the front nut, then loosen the REAR nut about a quarter turn, then have your helper push the brake pedal down very slowly. It should take him about 15 seconds to push it half way to the floor. Any faster, and the air might still get forced down the lines. While the pedal is moving down, you will see air bubbles coming out around the nut's threads. When the bubbles stop appearing, tighten the nut. Tell your helper to not allow the pedal to move back up until you tell him the nut is tight. Raising the pedal too soon will allow air to be drawn back in through the nut's threads.

When the nut is tight, tell your helper to allow the pedal to come back up QUICKLY. The brake fluid rushing back to the reservoir will wash any air bubbles back too. Do this procedure a second or third time until you don't see any air bubbles, then do the same thing to the front brake line.

As long as the brake pedal is pushed down very slowly, no air will be pushed down the steel lines. The fluid will go down, and the air bubbles will float back up. When the pedal is released quickly, any air bubbles that stick to the lines will be drawn back up to the reservoir.

Fill the reservoir with clean brake fluid from a sealed container to the same level as was found in the old master cylinder. If the level was fairly low, that's what happens when the front brake pads are worn close to the end of their life. Installing new pads results in the fluid returning to the reservoir and the level will go back up to "full". If you fill it before that, the fluid will spill over and make a mess when new pads are installed.

Caradiodoc
Jan 6, 2013.

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