Bleeding brake system 323 GTR

[prizmatik]

Hi guys. I am having big issues bleeding my brake system on my 323 GTR jdm with ABS. As you guys know, the GTR master cylinder is electrical, not mechanical. During winter season I installed stainless steel lines and changed fluid for DOT4. I started the bleeding procedure as if it was a normal car, from back to front, with the ing. key on so that the actuator pump would pump the fluid thru the lines. After beeing sure there was no more bubble, I tought I was done. Still, pedal was going to the floor.

I got my hands on the right procedure found in the GTR shop manual (thanx to Robert Green) and realized that I need to start with front with the key off, then move to back with the key on, so that's what I did. Same results at the end, no pressure. Then I decided to change the master for a spare one. That's what I did, after I redid the exact same procedure called in the shop manual, with the exact same result. What are the odds that both masters are busted? I haven't found leaks in my system, we bled more than a liter of fluid to make sure they was no air anywhere.

Did I do something wrong? Someone here had to do so on his GTR and has a trick or knows something I dont? Some people tell me to use a vacuum system to bleed, other say not to cause it will bust the seals inside the master...

Please anyone help me with this, I a am discouraged... Thanx.

[FE3-323]

i've done the same thing as you, but without the extra ABS module & had no luck until i put a vacuum onto it.
the trick with using a vacuum pump is not to push the brake pedal when you're using it.(that will cause issues)

[prizmatik]

Mazdasly75 told me to do the exact same thing but with the key on.

[Rivet]

What might be happening is that you have air stuck in the abs unit. You usually need to bleed the brakes conventionally, this will push air into the abs unit. Bleed the abs unit. Not sure on the GTR, but this is usually an automated process where the ABS controller runs the pump and cycles the ISO and DUMP solenoids to push air out of the ABS unit and then finally, antoher conventional bleed to get the air completely out of the system

[prizmatik]

Is there a procedure to bleed to ABS unit??

[Rivet]

If you look in the GTR supplement, page P-7; the rear brakes are bled with the key-on, and the abs pump should run. The pump should push air out of the abs unit. The key to this is to follow the WSM procedure exactly.
It's been my experience that Mazda ABS systems are very forgiving when it comes to brake bleeding, but the GTR is something different, so maybe it is sensitive to bleeding procedures. If the WSM procedure does not work, then you'll need to take a step back and recheck everything. Make sure the calipers are on the correct side (bleeder screws on top), brake hoses are good, etc.

[prizmatik]

That's the problem, I have already followed many times the shop manual sequence. And dont worry, my calipers are installed correctly since every thing was working fine last fall when I stored the car for winter...

[Rivet]

check out: http://www.brakebleeder.com/ I've never used this style bleeder, but it might be worth a try. You could also try a pressure bleeder (http://wiseautotools.com/brn-g300-pr...ake-bleeder/); the VW guys seem to use this style the most, so you might want to try a local VW shop. I've had the best luck with the snap-on BrakeKare machine (https://store.snapon.com/EEBR311A-Br...P643184.aspx); it pushes fluid into the master and pulls it out at the bleeders. But it's a $6000 machine and not many shops have one. Good luck and try not to get frustrated.

[prizmatik]

Thanx for the infos. For as not getting frustrated, I am about to put the car on fire... lol

[prizmatik]

Finally found out that my master is busted. Anyone heard about a conversion to get rid of that ****ty abs master to convert to a regular vacuum booster ?