Hi, I adjusted handbrake cable and after checking, the drivers side rear wheel is not spinning free on axle stands with handbrake off. I’m assuming it’s the caliper that has seized and nothing to do with handbrake cable? The cables are not in line with each other either. Is it easy enough to unseize a caliper? thanks
Usually, winding in the piston fully, then manually jacking it out with the lever where the cable attaches , frees them up. Might take a couple of goes, and some wd40 around the lever.
Thank Tristan. Got the caliper off. Had to free the handbrake bracket so it moved by hand. Problem I’ve got now is I can’t get the rubber sleeve back into caliper for the piston. Nightmare.
Haha. Did it eventually! Now need to bleed brakes as pedal goes to the floor now. Will have to find tutorial on bleeding brakes.
I put Mk4 ones on mine (same as Mk3 just aluminium apparently?). Checked the Mk3 ones afterwards that had been stood 17 years and they still work OK so good for a spare set!.
Been mentioned a good few times here, but the best way is to wedge the rear pistons with a wind back tool, hang the caliper as high as the flexi allows with the bleedscrew pointing up, and tap the caliper with a spanner a few times when you open the bleedscrew. Even before you start pumping I'd not be surprised if you didn't get some air out. I learnt that on here, many years from the legendary Danster. I'd ran litres and litres of fluid through a mk2 , tried pressure and vacuum bleeders, was convinced the (new) master cylinder was faulty, until I tried Dansters method. It's worked on loads of mk2s for me since, and everyone has been sceptical then shocked when it works. I presume you have the load sensing valve locked while bleeding? Also , in my personal experience, and not just mk2s but anything with that type of handbrake caliper, theres a way of getting the best pedal and the best handbrake action. You need to have the pistons out as far as possible, with the handbrake cable slack, and sometimes thats not as obvious as you'd think as the pistons tend to spring back in a lot when you let go of the lever on the caliper. Brief YT vid about it here. Not a VAG, but exactly the same type of caliper.
Here here, you passed that wisdom on to me when I was having trouble bleeding my rear calipers too, and it worked a treat.
Thanks Tristan. I've bled brakes and the pedal feels fine again now with good retardation. No, I didn't lock LSV. My car is lowered too. Will this be unsafe now cos I didn't lock LSV. I don't even know how to lock it. I wrote off a Mk2 when I was 19. Braked hard and it was like I pulled the handbrake up. A Mk2 enthusiast told me it was because I lowered car and didn't adjust the brake bias valve.
You're supposed to lock the bias valve to bleed the rears, to ensure full flow. If you raise or lower from stock you're supposed to adjust the valve also.
The pop rivet needs to be bent into a 'U' shape, the 2x holes don't actually line up when you squeeze the arm in as far as it'll go to get the valve to the fully open postion. That's just what I used, anything to draw the arm in / hold it there'll obviously have the same effect. Near the bottom of the thread here... https://www.clubgti.com/forums/index.php?threads/the-unofficial-not-crap-tool-thread-but-they’re-actually-really-useful-and-cost-1-3-of-the-price.293419/ There's no adjustment on the valve itself, if you do need to reset things that's done by changing the extent of travel via the brackets slot for the separate, large spring found between it and the beam.
Thanks gents. Might have a go at bleeding rears with valve locked. Unsure which way to adjust valve to compensate for car being lowered? It's on Koni STR.T Performance Suspension Kit -30mm lowering.
Jack the car a couple of inches, note the position of the lever, lower it and look again. You want to be adjusting it towards the position when the car is jacked.
I did this almost 2 years ago using Bentley, so get the following double checked in case my recollections a bit off (very likely). To have done it by the book I'd have needed 2x gauges that'd allow me to set things to specific pressures at the front and back calipers... not possible with the tools I'd access to, so wasn't going to happen! Starting point was to have the car on it's wheels / level floor and a full tank of fuel, but no one in it, presumably to try and emulate normal ride height as best possible. That'd be the conditions you'd want so that they coincide with regulators base setting. If you watch your regulator while someone else presses the brake pedal in and out a few times (while out of the car) you're supposed to see the mechanism move a little, think that just indicates at the very least things arent seized before you waste time going any further. I set mine up so that each spring end was at the point where it'd just start to be pulled if the lever were to be moved further. There's a nut / bolt / wheel affair that can be loosened to adjust the spring ends position along a short slot. Doesn't look like a lot of scope but was plenty enough for my particular set up. The make of my 'new' regulator meant it had a fixed stud attaching its own stumpy arm to its main body, I noticed there were others that instead were attached using a threaded nut. I believe that nut's not to be tampered with and is only there for initial factory set up. I was working on the basis the regulators natural (the holes are farthest apart) position is at it's most restricting, that's to say the front / rear bias is factory set up a for lone driver / full tank. As the car's weight increases, it'll start pulling down on the spring, which in turn starts to move the regulator arm (progressively reducing the restriction on brake fluid flowing to the rear calipers / increasing braking ability). My car is on standard suspension and I was setting everything up from scratch. I'd imagine on a car that's being lowered, but the regulator spring isn't adjusted to compensate for the changed beam / ride height relationship it'd potentially mean you would have the regulator already partly open (less restriction on brake fluid flow) even at rest, meaning your rear brakes would be thinking there's a partial load when there's not. I suppose if the imbalance was great enough you'd effectively be driving what is an empty car as if it were fully laden and the rear bias would be over compensating / potentially locking the brakes under normal stopping. Probably as clear as mud, but makes sense in my head!
It definitely makes a difference, my gti was locking the rears like a mofo at a Trackday, that had 280mm front brakes, stock.rears, and only a 30mm drop. I nearly spun it a few times.
