300zx brake swap issues

[senger]

Here's the story. Brand new rotors (30mm) used 300zx brakes (iron 30mm, tested off the definitive 300zx brake swap), took the calipers apart, cleaned EVERYTHING (didn't rebuild, drift event in a week). Just got everything hooked up on my S13 knuckles, brand new swap lines. Long story short, I have bled the brakes, but the pistons wont retract. (Brake drag). Drift event is in a week and I can't let this stop the work on the car. Any help is greatly appreciated and yes I searched. Thanks!

[zeitgeist]

Needs a rebuild.

New lube and rubber

http://zilvia.net/f/showthread.php?t=447190

[anti tyler]

Rebuilding the caliper could have taken you less than a day to do and rebleed. Now you need to rebuild them anyway.

Just take them off and rebuild them.

[senger]

Thanks for the confirmation guys. Appreciate it.

[senger]

So I rebuilt the front calipers and installed everything back on. Bled the brakes. There is still brake drag, but it isn't as bad from before. I'm extremely confused now.

[anti tyler]

You're 100% positive the rotor is settled flush to the hub and there isn't any other reason why the pad is dragging?

I just did this swap within the last 6 months and I didn't run into this issue at all.

What're you using as a BMC?

[SidewaysS13ka]

hey man did you happen to use the 300zx backing plates or s13 ones on your knuckles, because if you used your stock s13 ones with 300zx rotors and idk if you used your s13 caliper brackets or 300zx ones, but ill get to that soon. if youre using your s13 plates you have to cut the lip off of them and cut out some where the bracket would sit, if youre using 300zx everything i literally mean everything for the swap there should be no problem even after the rebuild, there should be no problem. as for the using 300zx hubs and s13 plates you have to modify the plate to clear the bracket, because the 300zx hubs sit out a little further than s13 ones. what it seems like is that your e brake cable is too short and or too tight causing it to drag. sometimes you can get away with using your stock cable and sometimes you have to use gts-t cables because they are longer or the 300zx ones, also im not too sure if the z calipers have the cable bracket on them like the 13s do, but make sure your bracket orientation is right that could cause the cable to snap back uneven when you broke your e brake. hopefully some of my rambling helped.

[senger]

This is for the front calipers, sorry if I didn't clarify that. I'm close to 100% sure that the rotors are flush. I checked hardlines, nothing is kinked.

[anti tyler]

This is for the front calipers, sorry if I didn't clarify that. I'm close to 100% sure that the rotors are flush. I checked hardlines, nothing is kinked.


Again, what did you use as far as the brake master cylinder? if you pop the hood and take the cap off the master, when you push the pedal in and release it are you seeing the fluid level return to normal or no?

There's a possibility that the master is sticking, along with the running possibility that there are ongoing issues with your calipers.

I suggest for testing purposes get the tool from advance auto parts that safely pinches soft lines, and pinch your front caliper soft lines. (If they're not braided already) and see if the issue is your master cylinder.


I suppose another way to test would be to crack your bleeders on both fronts or one at a time, use a rubber tube to a catch device, and leave them open while pressing your pedal, then see if the master is fully extending and retracting as it should.

[senger]

Using the stock s13 master cylinder. My buddies pressure washed my bay before I painted it. Could water have gotten in and ruin the internals?

[anti tyler]

Using the stock s13 master cylinder. My buddies pressure washed my bay before I painted it. Could water have gotten in and ruin the internals?

Internals of what? there is a small chance water got in the fluid, but if you're using anything other than DOT 5 you'll be fine.


I strongly suggest going ahead and switching to a Z master now. there is a possibility that your stock master has a bad plunger on it, and it's hanging up on the inside of the bore of the master. POSSIBILITY. however it seems more far fetched than something being up with the calipers.