Haynes Forums  

Go Back   Haynes Forums > Haynes Roadster Forums > Running gear
FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 20th September 2011, 06:41 PM
Peter-C Peter-C is offline
Senior Member
 
Join Date: Jul 2008
Posts: 279
Default Bloody bloody bleeding brakes !!!

A couple of questions on brake bleeding.

How long is a long session ? Is it 10 Minutes, 20, 30 ?

Do you have to every tiniest bubble in the world out.

I'm asking because I'm getting absolutely nowhere. The brakes hardly work at all and the the pedals as spongy as buggery.

Am I doing it right, start at the rear nearside, undo the nipple 1/4 turn , press down pedal and then tighten up and release pedal moving on to rear offside, front near, front off. I've removed the brake pressure sensor and pumped brakes. Stll no change.

Any ideas please ?

Cheers

Peter
Reply With Quote
  #2  
Old 20th September 2011, 06:48 PM
flyerncle flyerncle is offline
Senior Member
 
Join Date: Mar 2008
Location: gateshead,near cobbly bit of A1 North
Posts: 3,188
Default

Tiniest amount of air will gve you a soggy pedal,air is compressable fluid is not.

If you have rear calipers make sure they are bled with the nipples upmost even if you have to remove and place them on the disc elswhere to bleed,if you have rubber flexy hoses clamp them gently and try pedal,let them off one at a time and you may find the air.
__________________
Cost : Little as possible.
Thanks : To those who by their generosity my build has progressed.
Its a handmade sports car not a flaming kit car !!!


If at first you dont succeed,avoid skydiving...

No parachute require to freefall,only if you want to do it twice.
Reply With Quote
  #3  
Old 20th September 2011, 06:56 PM
Peter-C Peter-C is offline
Senior Member
 
Join Date: Jul 2008
Posts: 279
Default

Cheers,

The rears are drums with new cylinders and the hoses are the braided flexible ones.

Another stupid question, I assume that you carry on with the first one till it is absolutely clear and then move on, rather than get it almost clear, do the rest and then start over again.

I remember AshG having problems ages ago, I think I'll beat that !!

I'm totally hopeless at brakes, I even sold a car because I was that frustrated with them.

Peter
Reply With Quote
  #4  
Old 20th September 2011, 07:31 PM
Davey's Avatar
Davey Davey is offline
Senior Member
 
Join Date: Dec 2009
Location: Telford
Posts: 1,040
Default

I'm nowhere near doing my brakes yet but this is my procedure for replacing fluid. I use a Gunsons easi blead and it never fails. First off I drain the old fluid using the easi bleed to force the fluid out starting with the wheel furthest from the master cylinder the doing the others finishing with the closest to the mc.

To refill, connect a hose to the nipple of the furthest wheel cylinder and put the other end into a jar or jug. Fill the easi bleed with clean fluid and pressurise. The fluid will rapidly be transferred into the system, as required top up the easi bleed. When fluid runs clear from the hose without too many bubbles close the nipple and move to the next nearest wheel and repeat.

Once you have done all wheels go back to the first one and go again. If the pedal isn't good then I usually leave it half an hour with te pressure off and then bleed the traditional way with an assistant pressing the pedal. Its never failed me yet.

D.
__________________
visit my website at www.cossie.davenewell.co.uk
Reply With Quote
  #5  
Old 20th September 2011, 07:43 PM
Cyberbeej Cyberbeej is offline
Senior Member
 
Join Date: Nov 2008
Location: Dalry,Ayrshire, scotland
Posts: 241
Default

Quote:
Originally Posted by Davey View Post
I'm nowhere near doing my brakes yet but this is my procedure for replacing fluid. I use a Gunsons easi blead and it never fails. First off I drain the old fluid using the easi bleed to force the fluid out starting with the wheel furthest from the master cylinder the doing the others finishing with the closest to the mc.

To refill, connect a hose to the nipple of the furthest wheel cylinder and put the other end into a jar or jug. Fill the easi bleed with clean fluid and pressurise. The fluid will rapidly be transferred into the system, as required top up the easi bleed. When fluid runs clear from the hose without too many bubbles close the nipple and move to the next nearest wheel and repeat.

Once you have done all wheels go back to the first one and go again. If the pedal isn't good then I usually leave it half an hour with te pressure off and then bleed the traditional way with an assistant pressing the pedal. Its never failed me yet.

D.
I would have to say i follow a similar routine to davids.
Reply With Quote
  #6  
Old 20th September 2011, 08:19 PM
Peter-C Peter-C is offline
Senior Member
 
Join Date: Jul 2008
Posts: 279
Default

Thanks lads

Adrian, I've sent a PM

Peter
Reply With Quote
  #7  
Old 20th September 2011, 08:28 PM
rdodger rdodger is offline
Member
 
Join Date: Sep 2011
Location: Manchester
Posts: 85
Default

I used to use an easy bleed but now use a vacum bleed on the nipple. Just put a turn or 2 of ptfe on the nipple thread and it works perfectly every time. Just top up the reservoir as you go.
Reply With Quote
  #8  
Old 21st September 2011, 10:58 AM
flyerncle flyerncle is offline
Senior Member
 
Join Date: Mar 2008
Location: gateshead,near cobbly bit of A1 North
Posts: 3,188
Default

As per previous posts,I sometimes use a large syringe on the bleed nipples.
__________________
Cost : Little as possible.
Thanks : To those who by their generosity my build has progressed.
Its a handmade sports car not a flaming kit car !!!


If at first you dont succeed,avoid skydiving...

No parachute require to freefall,only if you want to do it twice.
Reply With Quote
  #9  
Old 22nd September 2011, 05:43 PM
Peter-C Peter-C is offline
Senior Member
 
Join Date: Jul 2008
Posts: 279
Default Numpty

Had an idea today, the brakes were just as bad as last time I bled them, about the rod that attaches to the pedal, that depress the master cylinder. So I made 3 different sizes and randomly fitted one. The brakes now are 1000 times better.

I will have hopefully my last bleeding session and then I can move on to the stuck clutch.

What a dick !!
Reply With Quote
  #10  
Old 22nd September 2011, 07:46 PM
Talonmotorsport's Avatar
Talonmotorsport Talonmotorsport is offline
Senior Member
 
Join Date: Oct 2007
Location: Southminster Essex
Posts: 1,323
Default

Some times the problem is the rubber seals in the master cylinder, if you have had it sat in the corner for a while they dry out and start cracking. It may be worth weighing up the cost of a rebuild kit Vs a new master cylinder. The one thing I don't cut corners with on cars is the brakes, for the sake of 30-50 I would replace it one way or another.
__________________
Website http://www.talonmotorfabrication.co.uk/

Direct email phil@talonmotorfabrication.co.uk

talonmotorfabrication@gmail.com

Mobile office hours 07514098334
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 09:36 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.