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D2 - Axles, Brakes, Suspension and Steering Brakes, Springs, shocks, steering racks, steering columns, suspension arms, wheel hubs etc.

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  #11  
Old 29th March 2019, 07:44 PM
hunker7 hunker7 is offline
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Quote:
Originally Posted by MikkiJayne View Post
That is the exact symptoms of when I had a master cylinder fail due to the scenario I described. One circuit (ie one half of the master cylinder) failed so I had no brakes on FR and RL (or vice versa) and then once the pedal had almost reached the end of its travel, it braked on the other two wheels.

The brake fluid reservoir will take 2 bar if its not cracked or damaged. It'll expand quite alarmingly, but I haven't had a D2 one pop yet! You'll not push fluid through the ABS pump at 10psi.
I really hope it's not the master.

OK I'll take the risk and go to 30psi tomorrow. Should I have all 4 calipers open or?
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  #12  
Old 29th March 2019, 07:45 PM
hunker7 hunker7 is offline
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Originally Posted by HPsauce View Post
Diagonally opposed cylinders linked are part of the standard design of braking systems to ensure total failure is extremely unlikely. And have been for decades.

So the symptoms are to be expected from almost any braking system going wrong, the challenge is to work out exactly what the cause is.
That confirms what I've read on other forums. I'll try and push 2 bar in tomorrow and see If that works. Fingers crossed.
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  #13  
Old 29th March 2019, 07:48 PM
MikkiJayne MikkiJayne is offline
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Do one at a time. There is a specific order which I can never remember. I'll look it up.

Fingers crossed its just behaving like this because you have a load of air in the system
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  #14  
Old 29th March 2019, 07:51 PM
hunker7 hunker7 is offline
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Originally Posted by MikkiJayne View Post
Do one at a time. There is a specific order which I can never remember. I'll look it up.

Fingers crossed its just behaving like this because you have a load of air in the system
I found this on audiworld.

Quote:
2. Cars with ESP

Same as above, except pressurize the master cylinder to two bar (29 psi). This scares me to death, I have visions of splitting the brake fluid reservoir and making one heck of a mess. Also, the bleeding sequence is different on ESP cars,

left rear
right front
right rear
left front
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  #15  
Old 29th March 2019, 08:57 PM
MikkiJayne MikkiJayne is offline
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That looks right.

I did explode the reservoir on an A4 a few years back. They catch sunlight through the back of the bonnet and so the back of the reservoir was crazed from UV damage. I hooked the pressure bleeder up to it and it blew the top right off! I had to push the car outside and hose it down to get all the brake fluid off.

The D2 reservoir is completely covered by the bonnet though, hence why they have less tendency to blow up
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  #16  
Old 29th March 2019, 08:59 PM
hunker7 hunker7 is offline
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Originally Posted by MikkiJayne View Post
That looks right.

I did explode the reservoir on an A4 a few years back. They catch sunlight through the back of the bonnet and so the back of the reservoir was crazed from UV damage. I hooked the pressure bleeder up to it and it blew the top right off! I had to push the car outside and hose it down to get all the brake fluid off.

The D2 reservoir is completely covered by the bonnet though, hence why they have less tendency to blow up
Ok, that's given me bit more confidence. I'll let you guys know if it worked tomorrow. Fingers crossed.
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  #17  
Old 30th March 2019, 03:31 PM
hunker7 hunker7 is offline
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I assume it won't take long for fluid to come out? 2 bar and not s drop of fluid. Any way of checking master before I source one?
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  #18  
Old 30th March 2019, 04:39 PM
MikkiJayne MikkiJayne is offline
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Are you getting fluid from the other corner?
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  #19  
Old 30th March 2019, 04:39 PM
hunker7 hunker7 is offline
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Originally Posted by MikkiJayne View Post
Are you getting fluid from the other corner?
No fluid on rear left, getting fluid on rear right.
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  #20  
Old 30th March 2019, 05:08 PM
MikkiJayne MikkiJayne is offline
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Front right?
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