Brakes dragging and bad brake fluid

[jayb79]

If you replaced the rear calipers then you should first bleed them on the bench. I had a hard time getting my pedal to firm up until I did this. When bleeding my brakes the pressure system worked best if you don't have another person to help out. Also if you have someone standing on the pedal when you release the pressure bench bleeding my not be necessary. The new rear caliper is a bargain here, I bought a pair about 5 years ago and haven't had and issues.
https://www.europaparts.com/brake-caliper-1j0615423g.html

 

[BeetleDragon737]

Just searched bench bleeding and found this thread:
http://forums.tdiclub.com/showthread.php?t=430988

Seems like doing a gravity bleed to fill the caliper is as effective as bench bleeding?

 

[Nuje]

That's the steering knuckle, also known as the spindle. The caliper carrier is a separate bracket that bolts to the spindle with two large bolts(I think hex head,...

On the typical Mk4 TDI, this is NOT correct.
BeetleDragon737 - you are correct in that the caliper (#4 in diagram below) is replaceable; the pads slide on a "carrier" that is part of the steering knuckle.

 

[Mongler98]

If you replaced the rear calipers then you should first bleed them on the bench. I had a hard time getting my pedal to firm up until I did this. When bleeding my brakes the pressure system worked best if you don't have another person to help out. Also if you have someone standing on the pedal when you release the pressure bench bleeding my not be necessary. The new rear caliper is a bargain here, I bought a pair about 5 years ago and haven't had and issues.
https://www.europaparts.com/brake-caliper-1j0615423g.html

Look up ome man bottle bleeder.
Hose with a check valve that loops a few feet higher than the caliper. Cost, $5

 

[KrashDH]

Just searched bench bleeding and found this thread:
http://forums.tdiclub.com/showthread.php?t=430988
Seems like doing a gravity bleed to fill the caliper is as effective as bench bleeding?

You're really overthinking this.
I didn't bench bleed any of my brakes when I rebuilt, they all work fine. If you're worried, just fill the caliper with fluid prior to installing it on the car.

 

[jayb79]

You're really overthinking this.
I didn't bench bleed any of my brakes when I rebuilt, they all work fine. If you're worried, just fill the caliper with fluid prior to installing it on the car.

Aka bench bleeding.

 

[KrashDH]

Aka bench bleeding.

Nah, filling is not bleeding as far as the terminology I grew up with. But to each their own. I've bench bled closed systems out of a vehicle (manual transmission slave/MCs), which still involves removing air from the system and replacing it with fluid.
I suppose you could gravity bleed the caliper off the vehicle, but I've never needed to or see the reason to take it that far on the bench.
Tomato/Tomáto

 

[BobnOH]

There are several ways to do it right and several ways to do it wrong. Key is to understand completely how the hydraulic system functions.
I used my partner on the pedal for years, but evently I wore her out. Bought a Motive. Even with that, occasionally I've had to repeat the process to get the desired outcome.

 

[KrashDH]

There are several ways to do it right and several ways to do it wrong. Key is to understand completely how the hydraulic system functions.
I used my partner on the pedal for years, but evently I wore her out. Bought a Motive. Even with that, occasionally I've had to repeat the process to get the desired outcome.

In the last year with the projects I've had to tackle, I've been all about work "smarter" not "harder".

I purchased a unit similar to a Motive for bleeds. Seeing that I don't have someone most of the time to help me bleed brakes. I didn't put fluid in it though and just used it as a pressure chamber and it worked phenomenal (since I use it across multiple vehicles with different DOT fluid).

The other similar item I built was a custom gear oil/transmission oil dispenser. No more pumping quart bottles 100x per quart for any fluid changes. Adapted a tire valve into it so I don't even have to pump it up

 

[Curious Chris]

Power Motive pressurized brake bleeder is the best: load with brake fluid and attach to master cylinder and pump up to 10 psi; open the bleeders. On my wife's A3 I had to replace the wheel cylinders and no fluid would come out at 10 psi; so I pumped the brakes and really nasty brake fluid came out.