Rear disc upgrade = NO parking brake!

[hans j]

[dobryan]

[syncrodoka]

[Sodo]

[Sodo]

[hans j]

[insyncro]

I too can plainly see the issue.
Everything needs to be slack free to provide the hold everyone is saying they dont have.

[Sodo]

dang thats the problem with pictures..... sometimes you see stuff you're not supposed to see.

Cable slack is not the issue here at all. I'm 100% positive that if you pulled my brake handle, that you ALL would say this......

1) Hey this brake handle tops out hard but its too high. You can move the handle down by taking up some cable slack.
2) But no sense adjusting handle position yet, lets go see if your brake caliper actuators are pulling tight.
3) Yup the cable is pulling tight and might I say FIRKIN' tight. Yup the little caliper actuator is maxed out and it hasn't even gripped the disc yet. No point in fussing with the cable yet, theres some problem with the parking mechanism inside the caliper.
4) Oh wait, you have left some return spring on the end you must be coilbound! Ooops sorry I can see space between the coils....with all the long heavy, dangly cables in this vanagon setup an additional return spring will help; but could coilbind, keep an eye on that.

Positive!

===========================

Currently thinking is the auto-adjust inside the piston is stuck and not allowing the auto adjust to advance to the point where it can put pressure on the disc.

Here's the proper tool as seen in http://www.youtube.com/watch?v=SDeAwJrDlZk at minute 7:45

I don't have that tool but a needlenose plier worked OK. It was impossible to turn the piston until I freed it up several turns with a channellock. Then it screwed in with the needlenose. I think my auto-adjust is stuck because I haven't used the parking brake in years (because it didn't work). I pumped it back out with the footbrake. New brake pads will arrive this afternoon

After I get the caliper auto-adjust working the next task is to take up all of the cable housing slack and see if I can have a parking brake!
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[hans j]

You should see the piston move out when you manually move the arm the cable is connected to. It only has to move a little bit to grab the caliper.

It's very likely your cable could be hanging up on something else in the front part, or your park brake handle is just maxed out and stopping. The cable slack is an issue.

This is the park brake reset tool I have, but from the dealer http://vw.snapon.com/specialtoolsdetail.aspx?itemid=6840009 Why would I spend $65 on a tool just to push in VW/Audi rear brake pistons? Because it's my job and I've done hundreds of them... So I'd like to think I know something about rear disc brakes. And I can tell you from experience that the gap in your cable is an issue.

You may have other issues as well, but if I showed up with beer in hand when you asked me to look at it, that would be the first thing I would tell you to address. After that's fixed, we could continue trouble shooting. If you absolutely wouldn't touch the cable until you rebuilt everything else, I would leave you to it and probably go swimming or something else relaxing...
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1986 Canadian Syncro Westy TDI - 1989 Syncro Single Cab - 2001 Audi S4 - 1981 VW Caddy ABA - 1980 VW Caddy EV - 1973 VW T-181

[syncrodoka]

We are already there. I am going swimming.

[madspaniard]

You guys can come to my swimming pool, I have the beers, and the van is parked outside so can also tell me what to do with my ebrake

Good thread Sodo, Hans and Dobryan, keep this going, I want to see success here so that I can follow steps.
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1991 Westy auto w/ Peloquin TBD

"The only difference between me and a madman is that I'm not mad” - Salvador Dali

[insyncro]

Yes, for the love of God get this fixed so that when the next person complains of a non existent emergency brake we can direct them here.

Keep up the good work Chaps.

BTW, I have the same dealer tool...works like a charm.

[Sodo]

>> If you absolutely wouldn't touch the cable until you rebuilt everything else, I would leave you to it and probably go swimming or something else relaxing...

I guess I can't bring myself to "adjust the cable" .....again..... because its clearly not the problem. Believe me I started into this by adjusting the cable. How hard is that? One nut! Obviously the FIRST STEP of troubleshooting any cable operated brake and so easy.

The problem is bigger than that, and more puzzling. It's in the calipers, not anywhere in the cable.

How do I know its not the problem? Because when I pull the brake, the cable pulls tight. Out at the wheel, the caliper lever the cable is at tight against the stops as it can ever get. No cable adjustment can change that, its maxxed.

If you adjust it so the handbrake pulls up 5 clicks at a hard pull, it makes no difference in braking. The brakes dont work because the calipers are not grabbing the disc and its not related to the cable.

You guys don't get to go swimming yet you're not listening. The cable pulls tight. Not the handle, not the linkage, the cable is so tight it's like solid steel. Cable adjustment is ruled out, it's not the problem.

To solve this I need insight on how the the calipers do their auto-adjustment or what you do to initiate it. Only svenakela has touched on this so far but I don't really understand yet.
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[Sodo]

This of you with experience with these SPECIFIC AUDI BRAKES:

Are there any steps I'm missing to change the pads?

1) Remove old pads & cleanup the calipers for the new pads.
2) Retract the piston by turning it clockwise while pressing it in
3) Install the new pads
4) Set the slack in the parking brake cable

Now for "5" is there a proper way to reset the caliper for the new pads before you drive off? Is one way "wrong"?

5) Pump the footbrake
-- or --
5) Actuate the parking brake repeatedly
_________________


'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[madspaniard]

[Ian]

[insyncro]

As per cable:
When designing and purchasing custom cables you can have the properly mating ends, length and supports to provide a very nice fitting and smooth actuating cable.

[Ian]

I'm particularly interested in how rusty your slider bolts are because they look pretty rusty in the 'loose cable' picture.

_________________
All your Buses are belong to us.
Love and good roads!
IN LOVING MEMORY OF ROB CRESS 1968-2012
**ACHTUNG DO NOT USE AA BRAND PRODUCTS OR BUY ANYTHING FROM PACIFIC PARTS INTERNATIONAL IN CALIFORNIA**

[insyncro]

I was waiting for someone else to mention the rusted calipers as many feel only Eastcoast vans have to deal with rust.

Zinc chromate spray, sprayable anti seize, Fluid Film....all very cost effect coatings to keep brake parts from rusting and becoming difficult to dial in.

[svenakela]