UK-POLOS.NET - THE VW Polo Forum

Evening,

my offside rear brake is not completely seized on but it is rubbing enough to stop the wheel being spun by hand (i can turn it but cannot give it a good push, let go and it still spin, like i can with the other side). it's also building up a little heat - as to be expected.

Should i take the calliper off and put another on?

You could do that, but it's probably just a tight piston that will benefit from some lubrication with brake fluid and being worked back and forth

937carrera wrote:You could do that, but it's probably just a tight piston that will benefit from some lubrication with brake fluid and being worked back and forth

Do I just take it off the caliper then press the brake pedal to fully extend the piston then lubricate the exposed piston or fully remove the caliper and piston?

If I take off the caliper completely what is the procedure to avoid getting air in the system?

Thanks for the info!

Dan

Leave the caliper in place and remove the pads. Then remove the top off the brake fluid reservoir and press the brake pedal down so that the piston moves further than it did when the pads were in place, but not so far that the piston pops out. Then use a suitable lever to push the piston back into the caliper, you can remove the dust covers and apply some brake fluid to the exposed metal to help lubricate the piston as it moves. Repeat until the piston can be easily pushed back.

Do it this way and there's no need to disassemble or bleed anything. If you push the brake pedal too far the piston may pop out, in which case it is easier to clean, but does involve removing / bleeding the caliper. I can't remember if it's a single piston on those calipers, if so simply make sure that the floating part of the caliper is free to move and is not corroded or gummed up with brake residue before you attack the piston movement.

thanks very much for the info! it's a massive help.

i reckon its a single piston. hopefully doing what you suggest will remedy the problem - its still moving just not going back enough

It's easier and quicker if you can have someone else pressing the brake pedal while you push the piston back, you will probably need to do this quite a few times to free it off.

If the bleed nipple looks in good condition and can be released then sometimes loosening that can allow the piston to return more easily due to reduced friction as you aren't having to force the brake fluid back through the pipes to the master cylinder and reservoir. If it's not in good condition, then put some penetrating fluid on and allow it to soak. That way, when you need to remove it you have a chance that it will unscrew without snapping off which falls into the category of a right pain !

FIXED - pads had corroded and stuck to the carrier tight enough to create drag on the wheel. Grinded down the side of the pads to fresh metal and reseated.