Seized brakes

[killerme]

The van (turbo diesel 1600 1988 T25) had been sitting unused for a while and a weekend trip was marred by both front brakes seizing up until the whole system was red hot. By the side of the road, I managed to work about one and a half hours on each brake, with wd40, banging with a hammer, pushing and levering in and out. I managed to get them both functioning sufficient to get the van home.

Bit of a beginner, but I have worked on more modern versions of brake systems. I was wondering if anyone could give advice about what you imagine I should be doing when I set down to fixing them - (1) Same as I did on the road but with better tools and more time (2) Taking off the calipers and cleaning them up, with new seals or (3) replacing each caliper.

I am imagining that the system will be pretty neglected and the bleed nipples will be seized and will probably break, although I have already been wd40'ing them for about 3 weeks now in preparation.

All advice welcome from those who have serviced these many times!

[boatbuilder]

You can get rebuild kits with new pistons and seals.

[New Kentish Campers]

I had this problem on my old van. When I stripped the caliper down, I noticed that there was a lot of corrosion inside the fluid chamber, caused, most likely, by old brake fluid as it's hydroscopic, I. E it attracts water.

I could have repaired it, but instead replaced both calipers and the brake fluid. And, if your disks were getting that hot, check they aren't cracked or have warped with heat as mine were too, I ended up replacing them too, along with new pads.

[killerme]

cheers! but groan....

[killerme]

Incidentally, does anyone know a link to identify your brake caliper type. I know there are different versions.

[kevtherev]

Before you buy anything clean the calipers out properly
The reason it seizes is corrosion..
The rust under the seal prevents the piston from returning to it's uncompressed position
So.
Pop the piston out, by pumping it out.
Marvel at the mess in there.
remove the seal from the bore (remembering which way it sits in the groove)
clean out all the rust and debris from the groove
reassemble.
bleed the brake with fresh fluid

took me a couple of hours and I now have brakes that don't seize up any more

[killerme]

fantastic. very positive. Lets hope it goes smoothly....

[killerme]

I assume you take the caliper off to do this.

[kevtherev]

Yes, off the disc like you're changing the pads, but no need to take it off the hose.
Leave it connected.

Make sure you can open the bleed screw
If you can't then it will have to be disconnected, to drill the screw out.

[killerme]

thanx kev. much appreciated. next spell of good weather!!