brake bleeding issue...

[Archbish]

So having finished the suspension and Brakes, I thought I\'d bleed the brakes, so I have a properly finished part (just the ECU, Fuelling, exhaust, cooling, interior, paint, driveshaft, trim and stereo to go then... *grin*), and having done so, it would seem that all the brakes are pretty much on constantly. Enough so that I can shift it with difficulty (and I\'m no wuss!), and ended up having to push it back into the garage with my other car.

Now my question is:
- is this normal? When I\'ve bled brakes in the past, it\'s always been on a vehicle that can move under it\'s own steam, so I\'ve not had to move it. It kinda makes sense for the brakes to bind as part of the bleeding process.
- if it is normal, then presumably just jacking it up and and easing the pistons should do it?
- if it isn\'t normal, then what the hell?

[Prof]

If you\'re bleeding the brakes and have a bleed nipple open, all the pedal pressure should just push the fluid out the open nipple, unlikely the brakes would engage at all.
 
Sounds more like you\'ve got a caliper sticking/binding

[Archbish]

Hey Prof - thanks for the reply, but I dont\' think I explained the problem properly.

I\'ve done the brake bleeding, and got lovely clean fluid all over myself, the drive, tyres, etc., but the problem is that ALL of the brakes are binding now.  It\'s only moved about 5 metres post bleeding, but it does seem that all of the calipers have shut and not released.  The more I think about it, the more it seems that I just need to shift the pistons a little and all will be OK...

[David Nock (RIP)]

Nothing stopping the brake pedal coming up ie carpet? Sounds daft but I\'m surprised that you can hardly move the car. I think it should roll with just a \'swish swish\' noise from the pads on the discs at this stage. Master cylinder seal \'rolled\'?

[SiH]

Master cylinder seal \'rolled\'?

That\'s what I was about to say
Did you run the fluid dry at any point?

[Archbish]

The cylinder was empty for quite some time (about oh, two years...!!).  So what does a \'rolled cylinder\' mean then?

[SiH]

Did you press the brake pedal at all in that time? basically the seals in the MC may have flipped causign a lot of problems inside the cylinder. Theonly real solution to that is a new cylinder, or strip and refurb with new seals

If the cylinder was empty it\'s also possible that the seals have perished leading to problems

[Archbish]

Oh, that pedal was PUMPED *grin*  I wanted to force through the new fluid, so did the full bleeding process.

OH well, if it\'s a new cylinder, it\'s a new cylinder...  Thanks for the advice guys!

[David Nock (RIP)]

The procedure I\'d use for testing is to jack all 4 wheels up and see if the brakes are all \'locked on\'. Assuming yes, release the nipple of a front caliper - does that free that wheel off? Repeat for other wheels. Assuming that everything comes free, there\'s a pressure build up trapped in the system which can only come from the master cylinder seals or the brake balance unit. The test for the balance unit would be (I think)- Before you start releasing bleed nipples- the front drivers side caliper is OK whilst others are locked up. That\'s because that caliper doesn\'t go via the balance unit.
Sorry for rubbish write up, thinking as I type!

[Archbish]

No way - that\'s perfect!!

I\'ll let you know later what the outcome is...:yes