While driving the other day, there was just something odd about the way the car was driving, so I pulled over to look around. Well, I had the dreaded "smoking rear end". I nursed it home and checked it out. The differential area was incredibly hot.

When I got under it today, one of the brake pads on one side was loose while the other was tight. So, I'm assuming the loose side of the caliper is toast?

Is there anything that I can do to save it or do they not recover from this?

Another thing: Neither caliper had anti-rattle springs on them. should they have?

 

OOPS.

If the caliper is actually seized, internal seal replacement is the only true cure.

I would first try:

Release tje bleed nipple, take a long blade screwdriver, and attempt to lever the pad away from the rotor, thus pushing the piston back into the caliper. You might be lucky. Probably not.

If, when doing this push back, the escaping fluid is a dirty black gooey mush, then the caliper is toast, both of them. That black gooey stuff is water contamination.

Cradle out, do what is needed, repeat in 20 years.

Annual brake fluid flush will help a lot.

 

Do you know the history of the brakes on your car? My car is a 73 model and has had the rear brakes out twice in the past 47 years for maintenance. Have your rears ever been out? If not it is likely they have corroded pistons that will need replacing. You may have to drop the rear end to do this job. Do not be hesitant to do so, it is not that hard and makes servicing the brakes very straight forward. As I recall, there are no anti chatter springs on the rear brakes.
( just noticed that GF got in ahead of me with some better advice - do what he says)

 

^^^^^ I forgot the DRINK BEER part, always more productive.

 

It could be the flex hose closing up inside. I had that once.

Rob

 

Thanks to forum Sponsor S N G Barratt, here's the relevant parts diagrams and numbers showing Anti Rattle Clips on the front calipers but not on the rear calipers:









You can download their full XJ6/XJ12 Parts Catalogue here:
https://www.sngbarratt.com/us/#!/English/Downloads

When I've refurbished calipers, I've always used stainless steel pistons.

Graham

 

Similar thing just happened to me a few months ago. Exactly 20 years since the last rebuild. In my case it was from lack of use. I did drop the cage and sent the calipers out for rebuild. Don'f forget some other new bits too while you are in there.

 

I had a similar experience some years ago around 1997 with my 1980 Series 3. White smoke from the rear was really billowing out ! The heat had toasted the caliper seal as well as the diff oil seals. A set of refurbed service exchange calipers and new diff seals put matters to rights, I had the job done by a well-known shop in Birkenhead but I don't know if they dropped the rear subframe or not. That car is still running around since I sold it in 2002.

 

Ah! I see your problem, Dave....it's meant to go the other way round, sorry

 

Yes. After a while I figured that out.

 

I don't know the history of the brakes. The rotors don't look bad. I can't imagine that they are original. The dust cover on the side where the pad was loose is crispy, so that's not good. There's also some wetness on that side of the diff.

I've resigned myself to the fact that it has to come out. Now I have to just do it.

 

I had that on my series 2! The discs were red hot. Changed the flex pipes and all was well - luckily.

 

I can speak from experience that you SHOULD change your brake fluid on a schedule. If it goes in clear and come out dark - it needs changing! The moving parts in the brake system will gum up and fail. These moving parts include the pistons in each caliper, the master cylinder AND the balancing manifold where the master cylinder is plumbed to and then exits out to the front and rear brake lines. There is a piston in there that will gum up also. That's what I had happen and it locked up both rear brakes.


Brake balancing manifold (for lack of a better description). It also has the brake failure switch mounted in it.

This is what the piston looked like before.

This is what it looks like apart.