Back in February of this year I upgraded from 03 calipers to 07 g35 non-brembo calipers all around. Took off stock calipers and had fluid drip into a bottle on all 4 corners but never let the reservoir get empty. Installed 07 calipers / bracket along with new centric rotors and stoptech pads. Bled the system by 2-man method and everything went smooth. I noticed the pedal was softer than before and brakes engaged only after maybe 1/3 of the pedal travel. I only drive it maybe once a week so I left it like that.

Now last week I bought Stoptech SS lines on rockauto, much cheaper than any vendor by the way. I installed the lines and bled the brakes using the 2-man method again. Bubbles came out for a few seconds on each line and once I had a steady stream I closed the bleeder screw. The pedal now felt worse then before, very soft and brakes wont engage till the pedal is almost to the floor. I bled the brakes again using a vacuum bleeder that connects to my air compressor. Same results, no improvement.

Any recommendations? I've read some posts where people say the only way to do it on Z's is with a pressure bleeder like the Motive brand. Others say the 2-man method and gravity bleed work just fine.
I also hear about fluid being trapped in the abs system and only using an appropriate scan tool can fix it.

Any help is appreciated. Thanks

 

The Motive pressure bleeder is one of the best tools you'll ever buy.

 

I've done the 2 man, or in my case me plus the wife, aka the "brake b!tch" (her term not mine). Then used the Motive bleeder. Both work, but the bleeder is so much easier. There is no way gravity is going to get it all out.

While bleeding you know the trick about knocking on the calipers with a rubber mallet? The tapping encourages the air bubbles to get "unstuck" and burp out, seriously it helps. I think part of the problem is the bubbles are so tiny you can't really see them. I once put a flashlight behind the drain tube and only then did those small bubbles become barely visible specs.

Also I found it does take a lot of fluid - even when you think you've got all the air out more is hiding in there. When I switched over to my Akebono's it took nearly 3 bottles! I did about 2 bottles but the pedal was a touch soft, I drove around and things got firmer, but to be safe I put another full bottle thru the system. Only then did they get really super firm and react instantly to the pedal.

 

I gave up and purchased the motive bleeder on amazon with prime shipping lol.
I do know about tapping the caliper all around to free up some bubbles, saw it work when I gravity bled it. When the lines were off, I probably got air up to the abs pump. Hopefully this power bleeder works.

 

The Z seems to really like to hide air, if I do a component change that requires bleeding, I end up bleeding a few times shortly after. Even with my Motive

 

I did the same upgrade on my 03, and ran into the SAME issues.
https://my350z.com/forum/brakes-and-...le-in-car.html


I bled about 4 times with little results. What I ended up doing was just drive the car (I know, but I had to get to work). A few days in the brake pedal stiffened up and its perfect now. Never bled it again. You could try that?

 

I finally got a chance to bleed the brakes all around again but this time with the Motive Pressure Bleeder. It's been about 3 weeks since I last bled them and the pedal didn't stiffen up like what DarkCreep said. So after bleeding with the pressure bleeder, the pedal feels exactly the same. No stopping power until pedal is very close to the floor. While bleeding each caliper, I was not getting any bubbles and I bled each side for about 2 minutes. I noticed when I press the brake pedal with the car on or off, there's a vacuum sound.

Should I bleed the master cylinder? Air in abs pump? Bad master cylinder or booster? Check valve?
Im pissed off at this car, just did a JWT clutch kit, new wheel bearings, sway bars and links and I cant even drive it cause the brakes feel sketchy .

Bump

 

Lame question, but are the nleed valves pointing up? Are you running the bleeding tube from the valve to another bottle or bowl that's submerge the tube under brake fluid?

 

Yes bleeder valves are all pointing up. I'm running the tube to a poland spring bottle submerged in brake fluid. Shouldn't matter for pressure bleeding any way as the fluid is being pushed out and no chance of it sucking any air from the tube.

 

Sorry to hear that VeeCueZ33, I had that issue as well after removing the front calipers to repair the dust boots. I also got that "vacuum sound". I didn't have a motive power bleeder at the time, so after some failed 2-person bleed attempts, which I have done successfully in the past, I took it to Nissan and had them do it for $80 and it was perfect after that. It's just trapped air in your line, but at this point I would have thought that a Motive Power Bleeder would do the trick. You may just want to take it to Nissan. They hook it up to a machine that forces all the air out and pressurizes the system. PIA for sure.

 

^Thanks for the info, I have a friend who's a tech at nissan, he said in rare occasions they have to hook up the consult 2 scan tool to cycle the abs pump.

I decided to check the brake booster vacuum hose that exits the battery compartment and connects to the pass side of the intake plenum. I blew into the side that would be pushing air into the plenum and air is passing thru. Then I blew into the opposite side, from plenum to battery compartment and air wasn't going through. Is there a check valve in the hose? Any one know?