Author Topic: new master cylinder and brakes still sh!t  (Read 2320 times)

Offline tweed

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new master cylinder and brakes still sh!t
« on: 26 June 2009, 15:27 »
Got the car couple months ago, before I got it it had been sitting over a year. Brakes were soft, so I bleed them and still no better. I fitted a new mastet cylinder today, bleed the brakes and it's still soft. They are a tiny bit better, but I can't even get the abs to come on!  :huh:

The brake pedal goes really firm when I bleed them, but as soon as I start the car, the pedal goes soft :undecided:
Could it be something els? How and what order are you ment to bleed them? I have engine off, first wheel is passenger front, then driver front, passenger rear, driver rear. Is that correct?

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Offline Wayne

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Re: new master cylinder and brakes still sh!t
« Reply #1 on: 26 June 2009, 16:22 »
If it is going soft when you start the car it could be a servo problem.

Offline tweed

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Re: new master cylinder and brakes still sh!t
« Reply #2 on: 26 June 2009, 16:35 »
If it is going soft when you start the car it could be a servo problem.

How would the servo affect it?

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Offline Adam

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Re: new master cylinder and brakes still sh!t
« Reply #3 on: 26 June 2009, 17:24 »
There is a small pipe with a non return valve that provides a vacuum to the servo. If you can compare your breaks with an earli mini then that's your problem.

Down Hill From Here.

Offline tweed

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Re: new master cylinder and brakes still sh!t
« Reply #4 on: 26 June 2009, 20:22 »
There is a small pipe with a non return valve that provides a vacuum to the servo. If you can compare your breaks with an earli mini then that's your problem.

Ok I know the pipeyour on about, but where is the non return valve? how do I test it? blow down each end?

Also I took the rear calipers off, wound the piston in and out couple of times. When I put them back on I made it really tight, asif the handbrake was on. Drove it down the road and pulled the handbrake up ( could only just get it to click once and the wheels didn't even lock up. So I'm starting to think the pads are sh!t. Also when driving slow and gently putting the brake on, you can feel it brake, put they just don't bite.

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Offline tweed

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Re: new master cylinder and brakes still sh!t
« Reply #5 on: 26 June 2009, 20:25 »
Also I've drove to 100mph (privite road my nan is rich  :wink:) and broke hard, foot to the floor and they are shocking. I got them very hot, got back to mine and they stunk!! So that makes me think the pads have had it too.
What you guys think?

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Offline Adam

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Re: new master cylinder and brakes still sh!t
« Reply #6 on: 26 June 2009, 20:30 »
Did you not look at the state of the pads?

It could also be the break pipes......

Down Hill From Here.

Offline tweed

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Re: new master cylinder and brakes still sh!t
« Reply #7 on: 26 June 2009, 20:44 »
Yeah the rear ones are shocking, but the front's look new. I didn't take the calipers off the front, just bleed them. But the car has been sitting for over a year outside and they could be very cheap budget pads.

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Offline Wayne

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Re: new master cylinder and brakes still sh!t
« Reply #8 on: 26 June 2009, 21:07 »
If it has been sitting for a year then the rear calipers could be seized.
« Last Edit: 26 June 2009, 21:10 by Wayne »

Offline DOA

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Re: new master cylinder and brakes still sh!t
« Reply #9 on: 26 June 2009, 21:08 »
Stock brakes really dont like 100mph stops regardless of what car they are on lol (theres a lot of energy being dissipated there lol). You say the car was sat for a year? I take it the discs got pretty rusty as Ive had pads go off after clearing serious rust deposits from the discs. Your handbrake test wont show you much btw.
Oh and the servo amplifies the pressure the master cylinder outputs, if its gone the brakes will be crap as they will not be seeing the normal amount of force.