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PhoebusApollo
02-19-2006, 11:34 PM
First off, I searched and didn't find an issue identical to this.

I just replaced my rear brakes (OEM calipurs, rotors, pads, and goodridge steel braided lines).

We bled the brakes several times, until there was no air in the system, to the point where the fluid coming out looks "EXACTLY" like the fluid being poured into the reservoir. We even went back and did the fronts even though I didn't touch them, to make sure no air traveled down those lines.

While bleeding the brakes I would pump to press out the air bubbles and then my friend would close the bleedervalve and the peddle would be ROCK solid.

Here's where the strangeness comes in. After the brakes are rock solid, if you let them sit for 30 seconds or so the next peddle press ALWAYS travels to the floor. If you press again, it's ROCK solid, and every subsequent press is solid. But if you let the peddle return to the top of it's travel the next press will go to the floor.

After discovering this we bled the entire system again (4 pints of brake fluid in all were used). I can say without any doubt there is NO AIR in the system.

I'm pretty sure this is an issue with the master cylinder (I can't believe that air would only cause an issue with the first press and not every press), and I thought I read on here somewhere about an issue with the valve inside the MC that can be corrected. If no one is aware of this, what is my best option. And consider that the front set of these:
http://www.courtesyparts.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=CP&Category_Code=240sx_nms_gtrbrake

are being installed either this coming saturday, or the following saturday.

If it is the MC, should I replace with the same MC or is it better to use something from the Z32? If so what pitfalls (different lines, etc) do I need to consider?

I know this is long, so thanks for reading.

NI_YON_Zenki
02-20-2006, 05:00 AM
With any obvious increase in brake load, you're going to need to increase the payload, which means. balance out the whole system. .. .

Get the Z32 MC with this GT-R32 brake setup, you should be fine. .. .they are the same caliper load series, and they're just better then the stock setup you're confronting currently anyhow, in which honestly has nothing to do with current problems you're facing. .. .

Cause they're not installed yet ! ! ! !

From what i've read, it seems to me, either one of your associated lines are loose, or the bleeder valve is not tightened when the brake lever is pressed. .. .just troubleshoot the MC lines and the bleeder lines to the rear. .. .

sideview_180sx
02-20-2006, 05:07 AM
your problem is a failing master cylinder. As long as you keep stock rear s-chassis brakes you would not need to swap out for the z32MC. J-land S14s come with z32 brakes up front and non-z32 outback.

skip. shut up, and lay off the weed.

NI_YON_Zenki
02-20-2006, 05:22 AM
your problem is a failing master cylinder. As long as you keep stock rear s-chassis brakes you would not need to swap out for the z32MC. J-land S14s come with z32 brakes up front and non-z32 outback.

skip. shut up, and lay off the weed.

You best stop tryin to drop weed into your little scapegoat problems with me. ..

I can smoke whatever I feel, considering I don't smoke that often to begin with, muthafucka, keep this shit to yahself. .. .

tell me to shutup one more time. .. .

this is against my nature to post so publicly, so I appologize to those who read this, I hope this will not affect my relationships with the individuals I have come to know here, and those I will come to meet in the future.

sideview_180sx
02-20-2006, 05:43 AM
shut up. again.

NI_YON_Zenki
02-20-2006, 06:14 AM
shut up. again.

Say good bye to that in which you need pay'd back

I told you. .. .I don't tolerate ignorance

ThatGuy
02-20-2006, 06:25 AM
How about both of you SHUT UP and take it to PM. If you are having personal problems, keep it off the Forums. I don't want to have to talk to either of you again.

Sidenote: Zilvia.net does not condone the use and/or abuse of any illegal substance. We don't codemn, we just don't condone. :D

aznpoopy
02-20-2006, 07:24 AM
from the way you described the bleeding process you may have bled it incorrectly.

you do not pump the pedal and then close the bleeder valve.

with the bleeder open and the pedal at the top of its travel, you press down. then you tell your buddy to close the valve. when its closed, you can release the pedal. when he tells you he's opened it, you press down again. etc. for flush just keep adding fluid to the resovoir as it goes down.

if you do decide to get a new master cylinder, get the stock master cylinder for your car... not the stock master cylinder for some other car. you only get the m/c for another car if you have upgraded your brakes in such a way as to require a different brake bias.

PhoebusApollo
02-21-2006, 12:15 AM
What you describe is precisely how we did it. I was just saying as an example that when the pedal was rock solid, if he released the valve you could feel the presure let off, as in there is no way there was any air in the lines.

And the new R32 calipurs are going on ASAP so I think the Z32 MC is the way to go... anyone know if the lines need to be changed out too?

Oh and I'm really glad my post turned into the weed post :-P

PhoebusApollo
02-21-2006, 12:18 AM
PS: Thanks guys.