Problem with Z brakes....

[frigga]

A quick summary of what parts were installed:

- 30mm Z Calipers- 30mm X-drilled rotors- Front and rear SS lines to mate to the Z calipers

Alright, so it comes time for me to put everything on my s13, so I first take off the stock calipers and install the Z rotors and calipers. After that, I installed all the lines.

Then I bled the system quite thoroughly, in the order the FSM says. Double checked to see if all the lines were tightened, and began checking for leaks. There were none.

Bled the system again, knowing that because we've takin off all the lines, there must be a lot of air inside.

Here is the Problem:

Upon start up, when pushing the pedal down a few times, there was a very loud and noticable hissing sound coming from it.It felt nice at first, but as soon as I started to drive it out of my shop, and applied the brakes, the pedal went straight to the floor. It wasnt grabbing at all.

Checked for leaks again, and there were none.

I talked to a caliper rebuilder who personally has a 300zx and he said that it could be the seals between the two halfs of the caliper that were either broken or not torqued properly. I sent it out to him and had them rebuilt, and when we put everything back together again, same problem, only this time it made a little difference. Pedal was still going to the floor and not driveable.

If there is anything that I missed, or I should have done, can you let me know. If you can help me out as to what the problem is, it would be greatly appreciated.

[Tsukai240]

you need the z32 master cylinder. those clipers need more fluid than the 240 master cylinder can displace.

[frigga]

I was under the impression that both the 26 and 30mm had the same displacement pistons. If the 26mm can drive without the master cylinder, why wouldnt the 30?

[Tsukai240]

check this out it may help http://importnut.net/300zxbrakeswap.htm

[frigga]

I've checked all the websites out that have to do with the install. Its not the fact that its not fitting, because everything it fitting properly, its that its not working is the problem.

I think its the MC or booster thats gone, so im gonna have to try that.

[Tsukai240]

the hiss may be the booster

[ziggy682]

Where is the hissing noise coming from?

[PapaSmurf2k3]

you dont need a 300zx master cylinder for the 30mm brakes, I have them on my car with the stock 240 master cylinder.

[virus77]

Ive got it on my s14 with stock MC and it works fine, maybe the 89 MC is weaker, or its the booster

[buntavy]

Does anyone has a better way to install their ebrake cable beside clip them together??.. it's seem too short for S14...

[Def]

Did you completely bottom out the MC when doing the "pump pump bleed" method? On Hondas at least, if you bottom it out on the "bleed" step you can damage the seals of the MC.

Not sure if Nissans are the same way, but it seems like your MC might be toast due to the install, and the only thing that involves the MC is bleeding it.

[S13ChucKAT]

No... you still have air in your lines.. trust me.. it may seem annoying.. but did you bleed your rear brakes as well?... on my 200sx, i did the NX2K upgrade, and i had to bleed, literally for like 2 hours.. until i got every spec of air out.

[buntavy]

Ok try this.. this is how my dad and i did. First, i top up the fluid and start my engine. Then pump serveral times and press and hold it down as hard as u can. And my dad with bleed frnt left first. We did one side for like 4 times. But make sure to check on your brake fluid everytime you bleeding. Do all front and rear the same thing. Try that if that work. I just finished upgrading both front and rear and use my S14 MC. It's working greart. GoodLuck...

[msaskin]

Also if you still can't get it to bleed, make sure you installed the calipers on the proper side of the car. If you installed them on the wrong sides, there will always be an air pocket at the top corner of the caliper that you can't get out, so you'll never be able to properly bleed them.

~matt

[S13ChucKAT]

^^^that happend to me..and i felt like an idiot when my friend told me.

[Toddles82]

I hope he has his brake problems solved by now since this thread was started a month ago.

[msaskin]

^^^that happend to me..and i felt like an idiot when my friend told me.

Yeah, I was speaking from experience too

Took me a few days of staring at it and re-bleeding the brakes until it occured to me.

~matt