gti6 brakes and master cylinder losing pressure?

1. Aaron Saxperience Post Whore Joined: Jan 2008 ..... Posts: 5231 ..............

   #1 18th October 2010, 14:24

   worked very weel previously to me taking struts off etc for new shafts...
   
   GTI-6 brakes
   with a 23mm master cylinder
   
   it was leaking from the master cylinder to res
   so i took off put new seals in..
   
   
   I then bled the brakes(front)
   
   it will be very hard without ignition on
   then ignition on same.
   
   then i go for a drive and it goes soft.
   put if i pump goes hard.
   then straight away back to soft..
   
   By soft i mean
   loads of peddle travel then finally brakes....
   
   Any ideas???
2. Aaron Saxperience Post Whore Joined: Jan 2008 ..... Posts: 5231 ..............

   #2 18th October 2010, 18:47

   bumppppp
3. Mochachino Saxperience Hardcore! Joined: Nov 2007 Guantanamo Bay Posts: 28700 oyster card

   #3 18th October 2010, 22:56

   Check the vaccum hose to the inlet. Rebleed the brakes starting from the furthest away from the MC area.
4. user_16747 Banned Joined: Jul 2007 Posts: 4328

   #4 19th October 2010, 08:43

   You nee to bleed all the brakes not just the fronts!
5. Aaron Saxperience Post Whore Joined: Jan 2008 ..... Posts: 5231 ..............

   #5 19th October 2010, 10:56

   Is there another way of bleeding them due to the nipples looking like they are going to snap??
6. user_10176 Saxperience Post Whore Joined: Jun 2006 Ramsey st marys, peterborough Posts: 8288 Saxo's, Corsa (Daily)

   #6 19th October 2010, 11:30

   Hmm can get the nipples off get them replace, if they are bad it not expensive, sound to me that there is air and if you remove the mc then all needs re bleeding as stated.
7. Mochachino Saxperience Hardcore! Joined: Nov 2007 Guantanamo Bay Posts: 28700 oyster card

   #7 19th October 2010, 11:41

   Quote:

   Originally Posted by Aaron Is there another way of bleeding them due to the nipples looking like they are going to snap??

   As I said in PMs last night bleed through the brake hose at the caliper.
8. Dan-Jnr Infrequent Poster Joined: Mar 2008 Manchester Posts: 164

   #8 22nd October 2010, 09:46

   Check the no return valve on the servo is working.
   Rebleed the brakes.
9. user_31412 Established Member Joined: Feb 2009 ★ West / North Yorkshire ★ Posts: 1653

   #9 22nd October 2010, 17:52

   Just had this problem this week on my mates 306 HDI - same brakes as the 306 GTI-6 (Lucas i think?). It was sorted when I bled the brakes enough for the new fluid to come out of the front brakes (the rear callipers were taken off and the fluid drained anyway). I don't think the ABS unit appreciated the old manky DOT 4 brake fluid to the front and DOT 5.1 to the rear. It now works a treat.