Unable to bleed brakes (SOLVED) - Custom Brake Thread

[andyfreelandy]

No biggie! Thank you for checking

Didnt need to check. Not never ever seen one in my life !!

 

[xDParis64]

It's me again! Finally managed to find the courage to look at the rear brakes... I hate drums.

Found that the wheel cylinders feel like sh*te and don't return when pressed, they go no pressure from the pedal until about 3/4 the way down the pedal, I think either air got in there and can't get out out the internals are broken. Video here showing the cylinder that does not return and has no resistance!

You can see here it moves a bit but then stops there, I wanted to make sure I was thinking rightly. So went to the other side to ensure that was working and when pressed inward it returns back to its original position albeit slowly.

2 new cylinders are in the way.

Let me know if you have any thoughts on this...

 

[Stanleysteamer]

It's me again! Finally managed to find the courage to look at the rear brakes... I hate drums.

Found that the wheel cylinders feel like sh*te and don't return when pressed, they go no pressure from the pedal until about 3/4 the way down the pedal, I think either air got in there and can't get out out the internals are broken. Video here showing the cylinder that does not return and has no resistance!

You can see here it moves a bit but then stops there, I wanted to make sure I was thinking rightly. So went to the other side to ensure that was working and when pressed inward it returns back to its original position albeit slowly.

2 new cylinders are in the way.

Let me know if you have any thoughts on this...

None other than, yep, put new cylinders on. If not properly bled the air in them, which contains water vapour, adds to any rust problem. Also they work over such a tiny distance that even if you take them apart and hone them, they often simply don't work again properly. If you do take them apart you will see how amazingly gunked up they get.

 

[Stanleysteamer]

Never had any success with that methond on any car. 2 person method for me is:

1) open bleed valve & assistant pushes pedal steadily to floor & hold.
2) close bleed valve & assistant releases pedal.
3) repeat 1 & 2 until no bubbles on fluid.

Remember to check master is topped up regularly.

Depending on the system, for one-person bleeding, you can either use vacuum on the caliper valves, or ezibleed on the master. Some ABS system prevents these from working, so it's back to 2 peeps.

RAVE specifies your method for the freelander.

Or the very simple rubber tube with the bolt in the far end and the slit in the side. Cost peanuts and I use them all the time, I have even made one when I couldn't get one.

Eezibleed is an oxymoron. Gave up on mine when it refused to work but sprayed the engine bay with brake fluid. Tired it on various cars with no luck.

But each to their own!!

 

[xDParis64]

Thank you for the reply, didn't even think to take them apart! My pressure bleeder seems to work alright, but I'll be using the pedal next time to ensure I get full range of the master to ensure air is taken out of that, going to fit them next weekend, painting the new front calipers I got too... so pictures will be coming soon (still painting)

 

[Alibro]

Thank you for the reply, didn't even think to take them apart! My pressure bleeder seems to work alright, but I'll be using the pedal next time to ensure I get full range of the master to ensure air is taken out of that, going to fit them next weekend, painting the new front calipers I got too... so pictures will be coming soon (still painting)

A powered finger file is your friend to grind off the heads off the bolts. Unless they've been removed already sometime recently the heads will chew off and you have no hope of getting them out.

 

[xDParis64]

...Here we are again, this again didn't fix the issue...

Good news though! The pedal now feels different... Still not good, but before it used to go solid but be very spongy, now the pedal is very smooth does not feel spongy but it goes all the way to the floor, it also (with the engine on) has a hard time coming back up to me... This tells me the master cylinder is broken... which has already been replaced Guess I will follow @Alibro and @pscan.eu's advice and return the master cylinder sent to me by RimmerBros!


What I've done today;

- Bled Brakes
- Replaced Front Calipers
- Replaced Rear Wheel Cylinders
- Adjusted the rear shoes to be 1-2 clicks off too tight
- Bled the Brakes again
- Bled the brakes again
- And again
- Ran out of brake fluid
- Bought more
- Bled them again
- Bled the master cylinder
- Bled the brakes
- Tested the Brake booster
- Adjusted the Brake booster to perfection
- Bled the brakes

You get the point I also bled them with the 2 person method and pressure bleeding and even tried with both at the same time.

But as said the brake pedal now has no resistance with the engine on and with it off it still goes to the floor but it will build some pressure if you press it quickly but as you bring it all the way back up it loses pressure again. I spent a while googling and it seems to tell me that the seal inside the master cylinder is faulty as letting fluid to pass it as the pressure through the lines at the nipples is still fine and has good pressure.

Remember! I have no ABS

Any thoughts would be appreciated!

 

[xDParis64]

All of that and I am just an idiot :/

I was doing some more googling and someone said "make sure the calipers are the right way otherwise the bleed nipples will be at the bottom. Lo and Behold reviewing some of the videos we took.

That is the bleed nipple at the bottom of the caliper...

Swapped them to the correct sides and voila the pedal works again! Almost... It has this "dead space" at the top like 10%-15% of the pedal where there is no resistance but then becomes instantly solid like a rock! anyone got any ideas what that could be? There is clearly no air in the lines when bleeding and adjusting the shoes and brake booster made no difference?

Super lost where this could be... OH! Also we replaced the guide pins with brand new ones. I looked online and AI said that A few good stops will set the rear adjusters correctly and could resolve the issue?

Any ideas how to fix it? Would it pass an MOT?

 

[Stanleysteamer]

All of that and I am just an idiot :/

I was doing some more googling and someone said "make sure the calipers are the right way otherwise the bleed nipples will be at the bottom. Lo and Behold reviewing some of the videos we took.
View attachment 347815
That is the bleed nipple at the bottom of the caliper...

Swapped them to the correct sides and voila the pedal works again! Almost... It has this "dead space" at the top like 10%-15% of the pedal where there is no resistance but then becomes instantly solid like a rock! anyone got any ideas what that could be? There is clearly no air in the lines when bleeding and adjusting the shoes and brake booster made no difference?

Super lost where this could be... OH! Also we replaced the guide pins with brand new ones. I looked online and AI said that A few good stops will set the rear adjusters correctly and could resolve the issue?

Any ideas how to fix it? Would it pass an MOT?

Cannot beleeeve that you fitted them with the bleed nipples at the bottom.
Having a bit of spare travel is not a bad thing.

 

[xDParis64]

Cannot beleeeve that you fitted them with the bleed nipples at the bottom.
Having a bit of spare travel is not a bad thing.

The wheel cylinders needed doing as before the pedal was spongy I only installed the calipers wrong after painting them, not my proudest moment...

 

[Stanleysteamer]

The wheel cylinders needed doing as before the pedal was spongy I only installed the calipers wrong after painting them, not my proudest moment...

I get the feeling you may not be old enough to have gone through the stage of trying to bleed the rear brakes on an old style Mini where the wheel cylinders were often fitted like that.
I love the way you call cylinders in disc brake calipers "wheel cylinders". Maybe you ARE old enough to remember 4 wheel drum brakes!

 

[xDParis64]

I get the feeling you may not be old enough to have gone through the stage of trying to bleed the rear brakes on an old style Mini where the wheel cylinders were often fitted like that.
I love the way you call cylinders in disc brake calipers "wheel cylinders". Maybe you ARE old enough to remember 4 wheel drum brakes!

The rear brakes are Drums... When I refer to Cylinders I refer to the wheel cylinders in the drums at the rear, when I refer to calipers I refer to the Discs and pistons at the front

I am very young though, thank you for noticing!

 

[Stanleysteamer]

The rear brakes are Drums... When I refer to Cylinders I refer to the wheel cylinders in the drums at the rear, when I refer to calipers I refer to the Discs and pistons at the front

I am very young though, thank you for noticing!

I love the fact that you call yourself xdParis64 and in fact come from Fareham, which is just down the road from me in the UK. Although obvs we are in our Frog résidence at the mo!

 

[Alibro]

The wheel cylinders needed doing as before the pedal was spongy I only installed the calipers wrong after painting them, not my proudest moment...

As mentioned before make sure you have a power finger file before you start the brake cylinders.
As for MOT, where I am they only care if the braking is good enough.

 

[xDParis64]

As mentioned before make sure you have a power finger file before you start the brake cylinders.
As for MOT, where I am they only care if the braking is good enough.

Blowtorch sufficed though they almost went!

 

[xDParis64]

Coming back to this with some good news finally! We managed to take it for a drive on... private road

None the less I can safely say while there is that 10-15% dead-space at the beginning the brakes still work in that range maybe it's just the steel lines I installed? Anyway the brakes finally feel much better based on this whole thread what I think had happened is that the Rear wheel cylinders got all jammed up and stuck / seized and at some point the Brake booster had failed causing symptoms to mix and throw us off course.

But we replaced the following;

- Brake booster,
- Master Cylinder,
- Brake Calipers and hardware,
- Rear Wheel Cylinders,
- All 4 Rubber Brake lines to Stainless Steel Pioneer ones (Strongly recommend - Same as the Muddy mods ones but you can pick your colour https://www.pioneer4x4.com/product/...0Mzg4MDkkbzEkZzEkdDE3NTU0Mzg4MTkkajUwJGwwJGgw),
- Replaced some copper lines with stainless steel (the rest to be replaced soon)

I will continue to update this thread with my custom brake system as I will also be replacing the Brake proportioning valve with some custom ones for adjustment so I can adjust it for on and off road but I will continue that in my Brake Prop Valve info thread.

Be sure to see some of the following here;

- Stainless steel brake lines full replacement (All Lines)
- Painting Various parts
- Brake Proportioning Valve install

 

[Stanleysteamer]

Glad you got it sorted, well almost.
The dead space ought to be down to pistons moving through empty space until the pads contact the discs, and/or the shoes contact the drums. If calipers are properly built I cannot see how that can happen as the seals only distort minutely to pull the pistons back from the pads, so I'd be inclined to really adjust up the rear brakes.
Other than that I can only think that the leverage towards the master cylinder is out somehow. Is it possible to adjust the pedal? I don't know as I have never had to do it but I have had to on other cars.

 

[xDParis64]

Glad you got it sorted, well almost.
The dead space ought to be down to pistons moving through empty space until the pads contact the discs, and/or the shoes contact the drums. If calipers are properly built I cannot see how that can happen as the seals only distort minutely to pull the pistons back from the pads, so I'd be inclined to really adjust up the rear brakes.
Other than that I can only think that the leverage towards the master cylinder is out somehow. Is it possible to adjust the pedal? I don't know as I have never had to do it but I have had to on other cars.

Even weirder that it applies the brakes a fair amount in that dead-space, but I think the MOT guy will be happy enough compared to last time

You can adjust the pushrod on the pedal to the master, I've adjusted it a bit, but it is technically "Over-Adjusted" by about 0.5mm - 0.75mm so it is gently pressing on the master not enough to move anything or apply the brakes at all but that dead space is still there, I think there is air stuck somewhere that neither the pedal bleed or pressure bleed can get out...

 

[Stanleysteamer]

Even weirder that it applies the brakes a fair amount in that dead-space, but I think the MOT guy will be happy enough compared to last time

You can adjust the pushrod on the pedal to the master, I've adjusted it a bit, but it is technically "Over-Adjusted" by about 0.5mm - 0.75mm so it is gently pressing on the master not enough to move anything or apply the brakes at all but that dead space is still there, I think there is air stuck somewhere that neither the pedal bleed or pressure bleed can get out...

Are you sure that it isn't just that the return spring is weak, malpositioned or summat, the return on the pedal or master cylinder I mean.

 

[xDParis64]

Are you sure that it isn't just that the return spring is weak, malpositioned or summat, the return on the pedal or master cylinder I mean.

It's perfectly possible and worth considering! For now though I just need an MOT it's been 4 months since I last drove it properly, gonna give it a quick shoot up the motorway before the MOT, I will be sure to let everyone know how that goes... Concerned for the emissions but that is another thread