gringoal

2002 Audi Quattro A6 2.7T
Front Brake Pads Type FNR-G60

The problem is that when the pads are fairly worn, even though the wear sensors have not yet connected , the caliper assembly moves inside the outboard edge of the pad carrier. The pad carrier then blocks the rearward removal of the caliper. The piston needs to be depressed to allow clearance for the caliper to move out but as the piston is not exposed to allow the use of a piston compressor or clamp the only solution I can see is to open the bleed valve to allow easy compression of the piston with the edge of a screwdriver. I would prefer not to open the bleed valve due to the risk of air entering the system.
Any suggestions?

4Driver4

I open the bleeder to purge the old fluid, but it really makes no difference. There is little resistence even with the bleeder closed.

S4_Cinci (I S'edTFA)

old pad still in there to avoid any piston seal damage. Only rear calipers need to be screwed in due to parking brake functionality. Pushing the pistons back in will not hurt them. Be careful not to overflow the brake fluid in the master cyl. if you've added any over time.

BernieBenz

No reason to open the bleed valve when retracting piston. The system bleeds back into the MC.

gringoal

Thanks guys, I didn't realise the piston would be relatively easy to depress without being able to center the load on it while the bleeder valve was closed.

I guess even if I do have to crack the bleeder open
I can use the old trick of connecting a plastic tube to the nipple and running it into a jar half full of brake fluid to prevent air at the nipple