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  #1  
Old 9th April 2011, 03:10 PM
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geeman geeman is offline
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Default Brakes nightmare.....

Hi all, i havnt posted on here in a long time but have been getting along well. The car is close enough to finished, just a few odd jobs to sort out. One thing that really has got me stumped though is the brakes. I just cant seem to get them to work well. I have bled and re bled many times, and even bought a pressurised bleeding kit which made the bleeding process much quicker. However, i cant seem to get the brakes to stop at all. Pressure only builds after around 30+ pumps of the pedal, and from what i have seen there dont seem to be any leaks. I did have to reflare one connection, but that was it, i havnt seen any other leaks, but yet no pressure builds. Any suggestions?

I dont imagine the master cylinder has any issues, as it worked well when it came out of the donor, but i may be wrong. Im using the standard rear sierra drums as well.

Thanks
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Old 9th April 2011, 03:31 PM
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JakeH JakeH is offline
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mechanic speak...

seems to me like you have quite a bad pocket of air somewhere, seen this before and it can be a bugger to fix.

have you tryed bleeding the brakes from the furthest from the master cylinder first then next furthest and so on? (furthest being the longest run of brake pipe) this may cure your problem. if not im stumped!

EDIT: you could also try opening all the bleed nipples at once and leaving it to drip through for a bit, just be sure the reservoir is full all the time

hope this helps

Cheers

Jake
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Old 9th April 2011, 03:42 PM
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geeman geeman is offline
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Quote:
Originally Posted by JakeH View Post
mechanic speak...

seems to me like you have quite a bad pocket of air somewhere, seen this before and it can be a bugger to fix.

have you tryed bleeding the brakes from the furthest from the master cylinder first then next furthest and so on? (furthest being the longest run of brake pipe) this may cure your problem. if not im stumped!

EDIT: you could also try opening all the bleed nipples at once and leaving it to drip through for a bit, just be sure the reservoir is full all the time

hope this helps

Cheers

Jake
Hi, yep, have always bled in the logical ordar, furthest away first. Im happy to try anything that may get it to work at the moment.

I have now got through my first 4 litre can of fluid but Ill keep giving it a go and see what happens. One thing i notinced is when using the prussurised bleeding kit(20psi) once i finish bleeding but without having removed the kit, the brakes work relatively well and only take around 2-3 pumps of the pedal to get firm, however this would be expectd as it is pressurising it to 20psi.

Thanks.
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Old 9th April 2011, 04:04 PM
js1uk js1uk is offline
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Sounds like the fluid is getting past the master cylinder plunger seals, so when you are pressing the pedal, it is not moving the brakes.
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Old 9th April 2011, 06:12 PM
mark mark is offline
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Sound like master cylinder to me, quite a few m/c failures have arisen after they have been stripped from the donor and left dry for several months
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Old 9th April 2011, 06:32 PM
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geeman geeman is offline
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Quote:
Originally Posted by mark View Post
Sound like master cylinder to me, quite a few m/c failures have arisen after they have been stripped from the donor and left dry for several months
I guess ill look around for a cheap master cylinder as it may well be the case its gone bad then, however i just noticed that when i pump the brakes for some time, i realised fluid was seeping out of the top of the resevoir, even when the lid is on as tight as i could get it. Any indications as to what the problem may be?

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