Sticky rear brakes on my Series 3. Help!

Hi.
Here goes with my first post. I have never used a forum before so I hope I am observing all etiquette but if I have missed anything let me know.
I have put some info on the intro thingy but I will give you all a bit of background before I pick your brains.
After years of wanting one I got a short wheelbase series 3 about 3 weeks ago.
It was fairly cheap so of course there are lots of faults. The one that is baffling me at the moment is that the rear passenger side brake is sticking on. I eventually managed to bash the brake drum off and the wheel cylinder seemed really sticky and a little bit leaky. I got a new one, cleaned everything up, fitted it and bled it and it binds just as badly as the old one! The question is what should my next step be. Should I replace the flexible pipe to the rear brakes or is it time to refurb/replace the master cylinder.
Here is all the other info I can think of.
The vehicle has been standing for most of the summer.
None of the other wheels seem to bind.
When I had fitted the new wheel cylinder it was fine until I bled it then the rear piston seemed to push the rear shoe out and won't go back in. It's like there is pressure from the brake pedal all the time.
Before bleeding the brake adjuster worked well and I could feel every click. After bleeding it just turns freely with no feel at all.
I have compared the shoes and springs with the front brakes and everything is assembled correctly (or at least the same). The adjuster is towards the front.
The brake pedal is not spongy. When you pump the pedal the brakes bind worse. If you then leave them 24hrs it is possible to turn the drum slightly. Could the brake fluid be being pumped to the wheel cylinder but not allowed back and if so how come it's only happening on one wheel?
I can't see any leaks.
Sorry for the length of that post but I wanted to give you all the info I could think of. Thanks for looking and I would be grateful for any help. Over to you.

surely if the adjuster is turning freely the leading shoe has come off it? I had that on my s1 and when I took the drum off the prong on the shoe that hooks on to the adjuster had come off the shoe so there was nothing for the adjuster to connect to.

I had a binding rear brake on my chevy truck, new cylinder sorted it out, had to replace the linings too but that was as a result of them binding, all the extra heat didn't do them any good

With the drum off crack the bleed nipple and push the offending side of brake cylinder back in if it goes straight in fault is hydraulic possibly collapsed hose or badly adjusted master cylinder , but would expect the latter to affect all wheels.
Who's manufacture was the replacement Brake cylinder?

Lots of possible problems. Brake return springs on wrong (lots of posts about this) No play in the master cylinder operating rod (not letting the brakes return) badly worn bearings (trapping shoes between backplate and drum - yes seriously!)
If the shoes release when the bleed nipple is cracked it's hydraulic, if it doesn't it's a mechanical issue inside the drum.

As above on master cylinder adjustment, the push rod must have some play.
Have you had a good look at the pull off/ return springs in the drum ? Iv'e seen lots where a previous owner has got the assembly wrong, the next owner replicates what he took as correct on reassembly.

Thanks for all the advice. I wasn't expecting so much so soon. This is brilliant! The brake cylinder is a Britpart one. I'm starting to hear all sorts of bad things about them. Are they really that bad? If so how do they keep getting away with it? Sounds like I should test it as you say to establish whether it's hydraulic or mechanical. That will rule out half the potential problems. Maybe I should double check the other rear brake for binding? If both rears bind then would that point to a failed flexible hose? I have compared the assembly of the faulty brake(springs etc) to the front brake on the same side and they are both the same. Of course it could be that they are both wrong but the front does not bind.

LincolnSteve said:

Thanks for all the advice. I wasn't expecting so much so soon. This is brilliant! The brake cylinder is a Britpart one.

Click to expand...

Its hit or miss with Britpart. they are not a manufacturer but a firm that buy cheap and sell cheap but some of their stuff is original equipment, just depends on what they can put their hands on. Or so I am led to believe.

I always buy Lockheed Delphi cylinders from dingocroft Brake Parts for Land Rover Series 2 and 3 Page 1

reasonably priced and good quality, tried lucas/trw once but it was duff out the box

Just replacing the flex pipe on my 2a clutch because it has collapsed inside,so it can happen.

Just a quick update. I've been out tonight for another look. When I undid the bleed nipple the pistons on the wheel cylinder easily went back and the brake shoes settled back out of the way. The drum went on easily and turned without binding. Even the adjuster works again. So the fault is hydraulic. I will check the master cylinder operating rod and make sure there is some play and let you know how I get on. Thanks everyone.

there is also a slim possibility that you have a blockage in the pipe or union over the rear axle stopping the fluid from returning to the mastercylinder

i've obviously no idea as to when (if ever) that pipework was last replaced