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  #1  
Old 20th September 2011, 07:41 PM
Peter-C Peter-C is offline
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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
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  #2  
Old 20th September 2011, 07:48 PM
flyerncle flyerncle is offline
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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.
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  #3  
Old 20th September 2011, 07:56 PM
Peter-C Peter-C is offline
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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
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  #4  
Old 20th September 2011, 08:31 PM
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Davey Davey is offline
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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.
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  #5  
Old 20th September 2011, 08:43 PM
Cyberbeej Cyberbeej is offline
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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.
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  #6  
Old 20th September 2011, 09:19 PM
Peter-C Peter-C is offline
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Thanks lads

Adrian, I've sent a PM

Peter
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  #7  
Old 20th September 2011, 09:28 PM
rdodger rdodger is offline
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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.
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  #8  
Old 21st September 2011, 11:58 AM
flyerncle flyerncle is offline
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As per previous posts,I sometimes use a large syringe on the bleed nipples.
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  #9  
Old 22nd September 2011, 06:43 PM
Peter-C Peter-C is offline
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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 !!
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  #10  
Old 22nd September 2011, 08:46 PM
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Talonmotorsport Talonmotorsport is offline
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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.
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