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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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  #1  
Old 29th March 2019, 02:30 PM
hunker7 hunker7 is offline
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Default No brake fluid at the caliper?

Hi guys, have a bit of an issue, there is no brake fluid coming to passenger rear caliper? All other calipers are fine but that? Any ideas? Pedal is right to the floor. W plate.
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  #2  
Old 29th March 2019, 03:12 PM
MikkiJayne MikkiJayne is offline
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What were you doing to discover this? Maintenance of some description, or no braking force from that corner?
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Old 29th March 2019, 03:15 PM
hunker7 hunker7 is offline
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Quote:
Originally Posted by MikkiJayne View Post
What were you doing to discover this? Maintenance of some description, or no braking force from that corner?
Had both calipers off as handbrake mechanism was seized. Rebuilt, put all back together and bled the system, pedal was a little spongy but passed MOT. Came home and decided to bleed it again, some fluid came out and then just nothing, pedal went to the floor. First thought was caliper blocked, but nothing is coming out of copper line that goes into the flexi.
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Old 29th March 2019, 03:25 PM
MikkiJayne MikkiJayne is offline
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Does the front right bleed ok and have plenty of force?
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Old 29th March 2019, 03:38 PM
hunker7 hunker7 is offline
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Quote:
Originally Posted by MikkiJayne View Post
Does the front right bleed ok and have plenty of force?
All other calipers I can bleed with pressure bleeder, but pedal is right on the floor, very very light. There is some force (very little) at the very end of the pedal.
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  #6  
Old 29th March 2019, 03:52 PM
hunker7 hunker7 is offline
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Just double checked and FR caliper ain't bleeding either.
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Old 29th March 2019, 05:13 PM
MikkiJayne MikkiJayne is offline
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Puzzling. Diagonally opposed calipers not working are a sign of a bad master cylinder. That can often happen when bleeding with the pedal on cars that haven't had regular fluid changes as the moisture absorbed in the brake fluid corrodes the inside of the master cylinder. Its fine while the brakes are operating normally, but when the pedal is pushed past its normal position when bleeding, the corrosion trashes the seals and you lose one or both circuits.

What's odd is that you're getting no fluid with a pressure bleeder either. Are you using at least 2 bar on it? You need that to get through the ABS pump.
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