Can’t bleed brakes

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My 1999.5 mk4 TDI Jetta has had an intermittent dragging brake (passenger front), and I found I couldn't fully retract the piston in the caliper with a C clamp. Today I installed a new caliper & rubber line, thinking that would take care of it.

When I went to bleed it, I was not able to get any fluid (or air) to come down from the master cylinder at all. Barely any came out when I removed the old rubber line either. When trying to bleed, there's no air or fluid pressure no matter how much you pump.

When pumping the brake, I can hear gurgling from the master cylinder, and the fluid level doesn't go down. It seems like air got trapped in the master somehow, even though I'm certain it never ran out of fluid.

Also, after disconnecting the old caliper & line, I was able to retract the piston no problem, leading me to believe the issue was in the master cylinder to begin with.

Has anyone else had a brake issue like this?
 
Have you tried a pressure or vacuum bleeder or raising the front to try and release any trapped air between the caliper and MC???
 
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I would have said to replace the hydraulic/rubber hose but you've already done this.

Often when you can't push in the caliper piston, there is typically an issue with the hydraulic hose being chaffed on the inside, causing this check valve like action. Fluid will travel one way(pressing on the brake pedal) but not the other way(pushing back the caliper piston). Unless for example, you crack open the bleeder valve or in your instance, disconnect the brake line as you did.

This still tells me that there is a restriction in that area that need more investigation.

Sorry that I don't have more info.
 
I would crack open the connection where the hose meets the steel line and see if you can pump fluid out. If not, you have to work back towards the dist. block or ABS and find the restriction. Air will not hold back the fluid.
 
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Originally Posted by CourierDriver
Take your autos to a professional brake place....how important is your family nowadays.


I couldn't agree more! Think how catastrophic a brake failure could be.

Ed
 
Try stating the motor and then try to bleed it. Sometimes the ABS may have a stuck valve that would releaewhen you start it up. Had that on rear antilock on my Ford Ranger. Who knows maybe yours is similar.
 
Originally Posted by Ed_Flecko
Originally Posted by CourierDriver
Take your autos to a professional brake place....how important is your family nowadays.


I couldn't agree more! Think how catastrophic a brake failure could be.

Ed

What's a professional brake place? Midas?

I'm actually between shops (again), not sure who I'd trust for car work at the moment. Good mechanics are hard to come by. And aren't cheap, not that I hold that against them, but sometimes I wonder if shotgunning a bunch of parts instead of paying labor to replace only the bad part is net sum zero game.
 
I found with the S70 in my sig that I had to turn the key to the "run" position to bleed the brakes. I don't know why, but with no key in the ignition I had the same symptoms as you.
 
Originally Posted by HangFire
Clogged/pinched line or frozen ABS unit.

Yes exactly. Elementary troubleshooting to locate the blockage. Working backward from the wheel toward the MC, start opening connections and see where you have free flow.
 
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I had a problem with replacing a rear caliper on my truck, bled and bled it, just would not give up whatever air bubble it was. In frustration I decided that I'd take it to the shop, but did a quick check to see if I could gently drive it or if I would need a tow. The brake held well enough, but once I let it roll a couple of feet, darn pedal came up to where it should have been all along! Took a spin, bled one more time, all was well.

When I mentioned it to my mechanic he said that sometimes occurs, some of them won't work properly until driven.
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I've heard of some air bubbles being really hard to get out but not the idea of actually driving a bit.
 
Originally Posted by atikovi
I'd take the correct line off the master cylinder and see if fluid flows out. If not, replace the MC. If so, continue down looking for the blockage.


Do 99 Jettas use a brake combination valve? Would a caliper and hose change have triggered (pressure change) the combination valve to block flow to the front brakes? I suppose you could check this to see if the opposite, driver side front bleeds. If the opposite front caliper bleeds then it wouldn't be your MC, right??
 
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Originally Posted by supton
Originally Posted by Ed_Flecko
Originally Posted by CourierDriver
Take your autos to a professional brake place....how important is your family nowadays.


I couldn't agree more! Think how catastrophic a brake failure could be.

Ed

What's a professional brake place? Midas?

I'm actually between shops (again), not sure who I'd trust for car work at the moment. Good mechanics are hard to come by. And aren't cheap, not that I hold that against them, but sometimes I wonder if shotgunning a bunch of parts instead of paying labor to replace only the bad part is net sum zero game.

Go to any auto parts store and ask for 3 references on who they would reccommend for a brake job,,usually they will give you their favorites...worked for me in the past..
 
Ok, the fact that youve pumped it with no resistance means theres air throughout the system now. Youll need a pressure bleeder, a hand vaccum pump may work, but the bottle is so small that it comes with its going to take a long long time to get it out that way. I just dealt with this on an 05 X5 2 weeks ago, another shop put brake lines on and didnt let it gravity bleed for a bit before pumping. It took me 16 liters of DOT 4 to get all of the air out, along with activating the ABS pump about 100 times. One entire day on the lift, just bleeding brakes, I lost my mind. We would be getting nice clear fluid, Id activate the pump, and about 2 oz of clear fluid later, milky white air bubbles would come out. I seriously had to activate the pump about 25 times at each corner to get it all out. Id say start with a pressure bleeder, and work your way down the system, master cyl, abs pump inlet, activate pump a few times, abs outlet activate pump a few times, then each caliper activate pump 5-10 times at each caliper. Never had one that bad.
 
I appreciate all the advice! It is just this caliper that was stuck. I replaced both rear calipers a few weeks ago (which were completely seized) and bled them no problem. The ABS seemed to work fine when I could still drive the car.

Since I can't get a pedal at all, I'm thinking the master is at least breached internally between the circuits. I messed with it a little more after letting it sit a day or two. Still the same, fluid hasn't dropped in the master. Also, the pedal sometimes catches and doesn't return smoothly... I wound up ordering a new M/C from IDparts.

Seems pretty straightforward to install, just have to figure out how to get my VCDS scantool working so I can bleed the ABS... also, do I really need a motive bleeder? Is it unfeasible to bleed the old fashioned way?
 
Open bleeder and go inside. I had one at home that wouldn't bleed even with new master cylinder so I opened all blenders then checked periodically. Closed each that had fluid until all 4 flowed. Nice firm petal. Sounds like yours is a a bad line since only one wheel.
 
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