Front brakes not releasing

[Forkie]

Hi John. Yes, the ideas, suggestions are certainly running out - along with my patience, for what should be such a really simple task. New pads, fitted into recon calipers ( along with all the other many, many new parts) to replace the ancient, dacades old original parts, but which did actually work to a fashion.
Had not thought about thickness of paint. Regarding the caliper section for the pad - no issue with thick paint there - or anywhere - just the usual ' sneeze of gold'. The back plate of the pads do seem more than a sneeze. However , i will make these following points:
Now pistons are all home - no issues with pads falling in to place. Movement on both plains, all 4 pads.
Pads are Standard EBC Kevlar, C.W.
Calipers are recons exchange from C W.
I have measured a random pad earlier with digital caliper - thickness including backplate - 14.80mm , width of backplate at its widest - 88.36mm - bare in mind my Indy guy has already shaved the faces back along, also been rubbing for couple hundred local miles - not sure how that compares with an NOS pad.
Foot placed on pedal on engine start up - foot sinks a bit - tells me servo is operating.
Next - been out to my Indy guy this eve, he cannot believe i am still having issues. He reminded me what he had done:
Calipers stripped for checking due to long standing - no corrosion, pistons all good but polished as matter of course. Fitted all new seal kits - C.W.
M/C - replaced the ' new' seal kit i fitted years ago, fitted a new C.W. kit.
Shaved the pads in case they were a thou too thick - we all know what remanufactured parts are like.
He even left out the anti squeel shims as a temporary measure - to gain a tad.
His opinion, this evening, is it MUST be the calipers - or more likely the seals - not bringing the pistons back the 1 mm.
He asked if i had tried cracking off the bleed nipple - which he also tried back along - and as there is no difference, his opinion is it is not hydraulic - as was suggested here, so must be mechanical.
Any replies or thoughts to this update would be appreciated.

[Forkie]

And our ' better halves' scowl at us men for keeping ' all this junk'. How much now do i regret throwing away those ancient, cracked, glazed and so hard original pads for new pads, , and for sending away its original calipers for ' better, newer reconditioned ' ones. What id give now to have all that back - just to try it, just to see if when i release the foot pedal, the pads release from the discs.
The way i see my options is this:
1 C.W. - no stock of recon calipers.
2 C.W . - Willwood conversion at £1400.00
3 Rimmers - have stock of recon calipers - £250.00 ( after surchages paid).
4 Rimmers - a BCC ( who?) Conversion kit for circa £900.00
5 A kind, club member who has an influx of old but working original calipers, with used worn original pads, that im happy to pay to purchase and post down here, for me to just try.
What would YOU do?

[Forkie]

A complete top to bottom rebuild a few years ago of a Vauxhall 2.5 V6 engine prooved to be ' challenging' to say the least, but at least it worked afterwards. Sticking a set of new pads into a pair of Recon calipers into a T 2500 for the brakes to back off after application is an even bigger task however. I find that ludicrous if im honest.

[johnnydog]

I bet you are totally frustrated with this Nige - I admire your ongoing perseverance though being honest!!
Regarding the pads binding - I was thinking more of the paint thickness affecting the overall size of the backing plate when fitted between the top and bottom of the caliper (in a vertical plane) rather than the thickness of the pad material and backing plate combined measured in a horizontal plane when fitted (if that makes sense?).
Personally, I would definitely try the good used original/ genuine calipers, and try the worn brake pads initially before installing a quality known brand of nos pads.
I know many would be lost without the sterling efforts of Rimmers and CW, but from personal experience, the quality of some aftermarket / remanufactureed items is questionable to say the least. Without specifying particular items, I have returned remanufectured parts to both the above due to poor fitment. I'm not saying everything is below par - I'm certainly not - I'm just going off my personal experiences with certain parts have bought in the recent past.
So it's definitely nos original / genuine items for me everytime, although I accept I am fortunate to have acquired a vast stock of nos parts over the 45 years of ownership of these great cars, and I rarely have the need to buy aftermarket / remanufacturered or reproduced parts (luckily!).
I know which path I would be going down.....!

[johnnydog]

It's this aspect across the pad I was referring to,; querying whether the paint thickness was too thick at the edges (at each end of the arrow).
These are genuine nos Lockheed pads incidentally.

[Forkie]

Yes i got what you meant with the width, and they have plenty movement when inserted. Well yes if i had a pair of original callipers and pads they would be going on for sure, but unfortunately i dont. I will carry on with some more tests ( although all i think that i can do is swap the non return valve), and either hang out for a miracle find that someone is selling, or splash out even more cash on a conversion kit

[Forkie]

Would you happen to know the thread size where the brake pipe screws in ? We are wondering if we could fit any random caliper that has the same thread as the brake pipe, just to see if that caliper backs off as it should, which would then MAYBE give us an inkling that it IS the calipers at fault before throwing out another bucket of cash to no avail...

[Forkie]

Right - the very latest straight off the press !! Had an unexpected early day. Ideal - carry on with the tests then.
All pads back in, all have free movement.
Have not applied footbrake at all during this ' manual' stage of freeing up the pads, pistons back in etc.
Got another new pad fitting kit to go on, but for now just re using what was on there.
Wheels back on, both spinning free as a bird as i say. No scraping or anything.
Wheels back on floor - so much easier to push / pull about in garage.
Swapped out my original servo non return valve for the C.W. second hand one. Pipe back on.
Start the engine, get to normal temp. Apply the footbrake. It initially went down a tad further than usual but soon returned to normal.Applied brake a few times. Switch off.
Went to push the car - mmm bit more resistence. They back on again....
Jacked up pass side and yep - no longer free spinning - but not as bad as it was - i could move the wheel freely, but would no longer spin.
Move to drivers side - it albut still spins - way freer than the pass side. Right - that tells me an indifference between drivers and pass sides....
Re jacked pass side after - it albut now freely spins.....barely any rub at all....
How bizarre.....obviously all this has been done in the garage - so engine at normal temp, but brakes unused/ cold. Does this give any indicators? I am almost tempted for a short spin out tomorrow eve... .

[Mike Stevens]

I'm sure I can find some used calipers if that might help.

Having applied the brakes, jacked up one side and tried turning the wheel, does it seem to ease off a bit the more you turn it by hand?

I still think that the rotation of the wheels are what brings the piston/calipers back a fraction. Unlike brake shoes, there are no springs (that I am aware of) that will pull it all back in again.

Go for a quick spin and then when you've returned try to stop without using the brake pedal! Ok, well, just a light press. Then try and push/pull the car.

I always used to 'feel' how the car moved when maneuvering and after disengaging the clutch. Does it still run on a bit more or not? If not, maybe something is still binding.

I admire your persistence...

Cheers, Mike.

[Forkie]

Hi Mike - the offer of a used pair would be most grateful, if not just for testing purposes, and then returned - it might help retain the sanity a little.....will see how the next bit goes....
So i was going to have a little jolly for testing but as the weather has gone totally balmy again - for all of us i believe - as i work outside all day , i am.prefering the cooler and shadier aspects of the evenings right now - so i may try a short run over the weekend. She was certainly an awful lot lighter to push about in the garage when it was all freed off thats for sure !!!! Just popped out now and definately moves better than it did a week ago, and thats after ' applying' the footbrake the other evening. Cannot quite recal how much wheel turning i did, i was too ecstatic for them to be turning much better than they were!!!!!
I have had a few comments about my continued effort - when you only have 1 of these cars, that has been off the road for so long, and having spent a few pounds on it and a few hours ( plenty of both !!!!!!! ) to be stuck ( no pun intended) on something as daft as non releasing brakes is very, very frustrating. And for my lad too - he is keen as to get out in it.