My '71 has been laid up for a couple of weeks now due to an unknown brake fault. I was coming home a couple of weeks ago when there was a bit of a 'clunk' and the aweful sound of metal-on-metal (rotating). Thankfully it happened as I was braking for the speed bump just near my place.
I finally got some time to jack it up and spin the wheels a bit and found that the calipers seem to be locked on slightly on both sides. The wheels will spin, but you can hear the pads lightly scraping the disks.
I'm assuming it could be some lock in the pressure in the braking system?
If they do float, maybe the guide bolts have seized, or one may have even snapped. How does the pedal feel? Have you bled a little fluid to see if there is pressure?
The "bit of a 'clunk' and the aweful sound of metal-on-metal (rotating)" you described makes me think maybe a friction pad has separated from its backing plate, but unlikely for both sides to do it at the same time. Again, possibly a broken retaining/float guide bolt.
Pop a caliper off to be sure, and if the bolts are intact, see if you can compress the piston with a g-clamp (or maybe even the correct tool if you're lucky enough to have one!).
A POSSE AD ESSE.
I live in my own little world, but it's okay, they know me here.
PLease don't be sorry Craig. It might not be great news, but it's better than having no idea what's going on. At least I can try to figure out how to fix it now.
Yer I agree with the pad material seperating from the backing plate hence the clunk.
This can happen when the pads have been left sit wet for a long, really long time and the the backing plates rust underneath the friction material.
I seriouly doubt thered be much damage if the car was not braked on for too long after the clunk.
VW T1 & T3 calipers are opposed twin piston arrangements, are fixed mounted and do not float, if they are floating, they are attemptimg to fall off!
Im not a complete idiot, quite a few parts are missing....