Have I got air in my brakes? Ebay bleed kits?

dredgey Posts: 23
edited January 2013 in MTB workshop & tech
Avid Juicy 3's :oops:

Had to replace the pads front and rear. Got the old pads out fine, pushed the pistons back to make room for the new ones, pistons wouldn't go back enough (as I was pushing one in, the other side would come out). Losened the bleed screw slightly, pushed the pistons back more, tightened the bleed screw back up, got the pads in. Done. But:

Rear brakes all sorted and working perfectly, but the front brakes are failing to engage the pistons and the lever has gone all floppy- Have I allowed air into the system somehow? The fronts were a little spongey in the first place but I can now hear a squelching sound when I pull the lever. I'm 99% sure I need to bleed them but can anyone please confirm?

In the meantime I've taken a punt on one of these:
http://www.ebay.co.uk/itm/170975181981? ... 1439.l2649