A4 (B6 Platform) Discussion Discussion forum for the B6 Audi A4 produced from 2002-2005

BIG issue after Brake Master Cylinder replacement....grrr

Thread Tools
 
Search this Thread
 
Old 09-02-2008, 02:26 PM
  #11  
AudiWorld Expert
 
MikTip's Avatar
 
Join Date: Jun 2000
Posts: 29,355
Likes: 0
Received 1 Like on 1 Post
Default What was the issue that necessitated the replacement of the MC?

Could be your booster is bad?

Is there brake fluid in the booster?
Old 09-02-2008, 02:35 PM
  #12  
AudiWorld Expert
 
MikTip's Avatar
 
Join Date: Jun 2000
Posts: 29,355
Likes: 0
Received 1 Like on 1 Post
Default

You got the Power-Bleeder?
Old 09-02-2008, 03:11 PM
  #13  
AudiWorld Super User
 
diagnosticator1's Avatar
 
Join Date: Oct 2005
Posts: 6,127
Likes: 0
Received 2 Likes on 2 Posts
Default

Bosch 5.7 ABS doesn't require pump cycling to bleed system.
Old 09-02-2008, 03:13 PM
  #14  
AudiWorld Super User
 
diagnosticator1's Avatar
 
Join Date: Oct 2005
Posts: 6,127
Likes: 0
Received 2 Likes on 2 Posts
Default

Power bleeder pressure must be at least 2 Bar.
Old 09-02-2008, 03:21 PM
  #15  
AudiWorld Super User
 
diagnosticator1's Avatar
 
Join Date: Oct 2005
Posts: 6,127
Likes: 0
Received 2 Likes on 2 Posts
Default Be sure the bleeder screw at the calipers is opened fully, or about 1 turn open ....

to allow enough fluid flow rate to carry the trapped air in the system to the calipers. If the bleeders are not opened enough, the flow rate will be to low, and won't purge the air completely.
Old 09-02-2008, 07:45 PM
  #16  
Audiworld Junior Member
 
downhillracer's Avatar
 
Join Date: May 2007
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
Default Re: You got the Power-Bleeder?

if you can pump up the pedal then you definatly have air in they system!! Keep bleeding! sometimes it takes a long long time to get the air from the master cyl. out of the system..also you have to bleed from closest to furthest on out cars which is not normal so LF, RF, LR, RR and just keep bleading...if you still dont get anywhere you can bench bleed the master, just crack the lines on the master, push the pedal down and while you are holding the pedal down have someone close the line.
Old 09-02-2008, 07:46 PM
  #17  
Audiworld Junior Member
 
downhillracer's Avatar
 
Join Date: May 2007
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
Default Keep bleeding

if you can pump up the pedal then you definatly have air in they system!! Keep bleeding! sometimes it takes a long long time to get the air from the master cyl. out of the system..also you have to bleed from closest to furthest on out cars which is not normal so LF, RF, LR, RR and just keep bleading...if you still dont get anywhere you can bench bleed the master, just crack the lines on the master, push the pedal down and while you are holding the pedal down have someone close the line.
Old 09-02-2008, 08:14 PM
  #18  
Member
 
javanator's Avatar
 
Join Date: Oct 2003
Posts: 1,547
Likes: 0
Received 0 Likes on 0 Posts
Default I am not familiar with the necessary steps to follow when replacing MC in our cars....

it's been many years since I did one on any car. Do you know if our cars require the replacement MC to be bench bled prior to installing on the car? That's what I used to do on dual reservoir metal MC's on American muscle cars.
Old 09-03-2008, 06:50 AM
  #19  
AudiWorld Senior Member
Thread Starter
 
CO AVANT's Avatar
 
Join Date: Jul 2003
Posts: 926
Likes: 0
Received 0 Likes on 0 Posts
Default

Bentley doesn't say to bench bleed but I sure have a lot of air in my system still
Old 09-03-2008, 06:56 AM
  #20  
AudiWorld Senior Member
Thread Starter
 
CO AVANT's Avatar
 
Join Date: Jul 2003
Posts: 926
Likes: 0
Received 0 Likes on 0 Posts
Default I definitely have air in the system still, lots of it...

bled 3 motive bleeder containers full of fluid last night through the calipers and the bubbles would not stop. I am going to try to crack the lines at the MC and the lines at the abs / hydro pump and bleed that way. Might get messy though. Is it better to do this with the bleeder or by having someone press down on the pedal?

Thanks for your reply!!!


Quick Reply: BIG issue after Brake Master Cylinder replacement....grrr



All times are GMT -8. The time now is 06:30 PM.