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spongy brakes.

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Old 03-14-2012, 09:11 PM
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Default spongy brakes.

So I recently dropped my front axle
And in the process the front brake cables got detached and drained
And while it was empty my dumbass pressed the brake pedal twice

So I put the axle back on and bleed the brakes.still spongy
Bleed em again still spongy
So I figured with 140k on the engine it might be master cylinder
Replaced that and bleed it and it still seems spongy.

Any ideas?

Tmrw I'm gonna bring it in to my school shop and try bleeding it with the rear jacked up then with the front jacked up.and see if that makes it better..
Old 03-14-2012, 09:25 PM
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A brick under the pedal always firms it right up.


Seriously though, did you bench bleed the master cylinder?
Old 03-14-2012, 09:30 PM
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Originally Posted by xj wheeler
A brick under the pedal always firms it right up.


Seriously though, did you bench bleed the master cylinder?
x2
Old 03-14-2012, 10:31 PM
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Hoses don't just 'detach', they break. Did you put new ones on? Have you also tried bleeding the rear? I have some funky things with brakes before...
Old 03-15-2012, 09:57 AM
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Originally Posted by cookrw
Hoses don't just 'detach', they break. Did you put new ones on? Have you also tried bleeding the rear? I have some funky things with brakes before...
uhmm well seeing as they are made to be detachable from the calipers im gonna say your wrong.. and yea like mentioned i bled all 4 wheels ywice before replacing master cylinder and once after. today i plan on one more try.

and ya i did bench bleed.. but maybe i didnt complete it?
wouldnt bleeding the sytem with the rtear jacked up do the same as a bench bleed esentially tho?
point of a bench bleed is just to bleed with the master cylinder level isnt it??
Old 03-15-2012, 05:58 PM
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so i tried jacking the rear up untill the master cylinder was level,
then i vacuum bled all 4 brakes
( school shop had a vacuum bleeder that hooked up to an air hose and vacuumed the fluid out )

still spongy..
any ideas?

next week is spring break so itll have to wait till after
but if i still havnt fixed it by end of spring break ill go back in
and try pressure bleeding it. ( oposite of vacuum, push the air bubble thru from the master cylinder. )
Old 03-15-2012, 06:00 PM
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possible bad lines after coming detached as you calling it
Old 03-15-2012, 06:46 PM
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Nevermind

Last edited by xj wheeler; 03-15-2012 at 06:48 PM. Reason: see post
Old 03-15-2012, 10:10 PM
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Originally Posted by 96rokee
well seeing as they are made to be detachable from the calipers im gonna say your wrong..
I have got to see pictures of these. I have never heard of something like them.
Old 03-15-2012, 10:40 PM
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Default bleed combi valve

I had same issues. New everything but still bad pedal. I ended up having to bleed the combi valve and after that and re bleeding all four wheels I have good solid pedal. Brakes on these things suck *** anyway . But working to spec is way better than not.
Old 03-16-2012, 08:46 AM
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If you drained the master all the way it needs to be bled, as does the proportioning valve. Once those are bled you need to bleed all 4 wheels in the proper order starting at pass. rear, driver rear, pass front, driver front. If all this doesn't help you have a defective part, most likely the front brake lines. Could also be a bad brake booster. On my 98 I couldn't get a hard pedal for the life of me, until I blew the rear line because it was so corroded and ran a new line ( I would check all your hard lines and make sure they all look good. And if you have ABS there could be air in the ABS pump and that HAS to be bled with the proper computer system (computer tells it which valves to move and when to move.) No way to do it yourself.
Old 03-16-2012, 10:37 AM
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Originally Posted by DrShaggford
If you drained the master all the way it needs to be bled, as does the proportioning valve. Once those are bled you need to bleed all 4 wheels in the proper order starting at pass. rear, driver rear, pass front, driver front. If all this doesn't help you have a defective part, most likely the front brake lines. Could also be a bad brake booster. On my 98 I couldn't get a hard pedal for the life of me, until I blew the rear line because it was so corroded and ran a new line ( I would check all your hard lines and make sure they all look good. And if you have ABS there could be air in the ABS pump and that HAS to be bled with the proper computer system (computer tells it which valves to move and when to move.) No way to do it yourself.
bad brake booster would cause firm pedal.. not loose.?? am i wrong?

and yes i bled in the correct order.
starting furthest from the master cylinder and moving closer.
and its not abs..

i hope the pressure bleeder system fixes it..
Old 03-16-2012, 10:38 AM
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Originally Posted by cookrw
I have got to see pictures of these. I have never heard of something like them.
lol go look at the brake lines on your xj..
there all like this.. as far as i know.

right in the middle of the caliper on the back theres a line thats bolted to the caliper.. the bolt allows the fluid to flow thru it and into the caliper to work the fron brakes..
Old 03-16-2012, 10:51 AM
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Originally Posted by 96rokee

lol go look at the brake lines on your xj..
there all like this.. as far as i know.

right in the middle of the caliper on the back theres a line thats bolted to the caliper.. the bolt allows the fluid to flow thru it and into the caliper to work the fron brakes..
sounds like the way all brakes work
Old 03-16-2012, 11:02 AM
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Originally Posted by stev-o
sounds like the way all brakes work
im just trying to explain it to cookrw.


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