240playtoy Posted December 21, 2005 Share Posted December 21, 2005 I'm wondering how boned I am here. I've searched and found tons of articles on the reaction disk slipping out and causing brakes to be either "on or off" (no real stopping power then locking up of the wheels). I've bled the living hell out of my lines after installing a 280zx master and 4x4 and 240sx calipers (living hells = > a gallon of brake fluid). So, I took my master off my booster and took a couple pictures. I think it appears I'm missing the reaction disk, but I have trouble visualizing the descriptions from previous postings. here's the plunger that presses on the MC. I'm guessing the inner ring is left from the reaction disk... or I may be dumb... both are possibilities. here's the inside of the booster. Again, I'm guessing I'm not supposed to see that metal ring there in the middle. So, dissassembly or new booster?? The brakes are the last thing keeping me off the road. And on the road is where I reeeeeeeaaaalllllllllllllllly want to be. Quote Link to comment Share on other sites More sharing options...
johnc Posted December 22, 2005 Share Posted December 22, 2005 Yup, you are correct in all of your assumptions. If you shake the booster you might hear it bounce around inside. Get a small flashlight and a small part gripper thingy and you should be able to fish it out of the booster. Quote Link to comment Share on other sites More sharing options...
Ed260Z Posted December 22, 2005 Share Posted December 22, 2005 When it comes to your brakes my opinion is to take NO short cuts. The booster looks preety run down. Spend a few hundred and get a rebuilt one. Quote Link to comment Share on other sites More sharing options...
240playtoy Posted December 22, 2005 Author Share Posted December 22, 2005 Thanks for the help guys. Off to get a new booster. I hope the pics help others figure out if they're missing their reaction disk. Maybe my Christmas present will be a 240z that will stop. Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted December 22, 2005 Share Posted December 22, 2005 When it comes to your brakes my opinion is to take NO short cuts. The booster looks preety run down. Spend a few hundred and get a rebuilt one. X2 Mike Quote Link to comment Share on other sites More sharing options...
J__ Posted July 24, 2006 Share Posted July 24, 2006 how did u take the plunger that pushes the MC out? just yank it out as hard as u can? i tried to pull mine out but was pretty tight, didnt want to break anything. Quote Link to comment Share on other sites More sharing options...
240playtoy Posted July 25, 2006 Author Share Posted July 25, 2006 Mine pretty much fell out. Just grabbed the plunger out it came w/ my finger strength only. I believe there was some sort of retainer "clip" in it. If I still have it laying around, I'll try to get a picture of it. Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted July 25, 2006 Share Posted July 25, 2006 Search... there is a thread about the boosters and how to get a kit and do it youself if you don't want to spring for a new one, with pictures and everything. Quote Link to comment Share on other sites More sharing options...
J__ Posted July 25, 2006 Share Posted July 25, 2006 i dont want to redo the whole booster, just want to pull the plunger out to see if the disk is still there. if not i'll fish it out with a tool. want to do all this with the booster still on the car. Quote Link to comment Share on other sites More sharing options...
240playtoy Posted July 25, 2006 Author Share Posted July 25, 2006 after I got my booster off the car and the plunger out, I just shook it for about 10-15 seconds and magically, my reaction disk fell out. I think I was just lucky. Of course, this was after I purchased a rebuilt booster. Quote Link to comment Share on other sites More sharing options...
J__ Posted July 27, 2006 Share Posted July 27, 2006 so can i pull the plunger outwards with the booster on my car without taking it apart? Quote Link to comment Share on other sites More sharing options...
240playtoy Posted July 29, 2006 Author Share Posted July 29, 2006 I looked at my old booster, it seems that either I didn't have any retainer holding in the plunger or I lost it. the area surrounding the plunger was a piece of metal with a rubber gasket covering it. It pulled right out without issue. Quote Link to comment Share on other sites More sharing options...
J__ Posted July 30, 2006 Share Posted July 30, 2006 yea theres a clip around it. the clip kinda looks like a sprocket. i pried it out with a flathead screwdriver and the rest came right out. my reaction disk was still stuck in place but i pried it off and super glued it down just in case. put everything back together and the brakse still feel like crap... no resistance till bottom out....... Quote Link to comment Share on other sites More sharing options...
240playtoy Posted July 30, 2006 Author Share Posted July 30, 2006 If you "upgraded" to the ZX master cylinder, your rod may not actually be touching the back of the piston. I found mine hissed and wasn't firm until I was about 1" from bottoming the pedal on the floor. There was over 1/2" between the rod and the piston when I measured. Here's a quick little writeup that I posted a while back, but it seems you know about it (you were the only one who posted). So what issues are you trying to fix (description of sounds, pedal pressure and braking)? Quote Link to comment Share on other sites More sharing options...
J__ Posted July 31, 2006 Share Posted July 31, 2006 yea i read ur writeup and adjusted my push rod. but i didnt measure it. i just extended it approx that amount, then i found when i put on the mc it was too much and pushed the cylinder when the MC fully against the booster. i then shortened it bit by bit until it didnt push on the cylinder, at that point i assume the rod was perfectly against, but not pushing the cylinder at rest. then bled the brakes to shitz, yet my brake pedal has a super soft linear feel until it bottoms out and brakes lock up. the classic "missing reaction disk" feel... but the thing is my reaction disk is in place and super glued down.... i posted my problem on forrest's thread here http://forums.hybridz.org/showthread.php?t=113035&page=2 Quote Link to comment Share on other sites More sharing options...
240playtoy Posted August 1, 2006 Author Share Posted August 1, 2006 ich.... Which brakes lock up, front, rear or all? Then there's the common question I've seen asked "are you bleeders on the top of your calipers?". I have a feeling I'm not going to be of any further help. I'd recommend starting up a post about it with everything you've learned is not the problem. Quote Link to comment Share on other sites More sharing options...
J__ Posted August 1, 2006 Share Posted August 1, 2006 well i havent gone fast enough to actually lock up all breaks and screech to a stop. but it's "no braek, no brake, no brake, then sudden brakes when the pedal hits the end. and yes all 4 bleeder nipples are at the top. as for hte new post, i have pretty much the same problem alot of ppl are having that posted on forrest's site, but no one has figureed out a solution yet. so i dont really want to start a multiple post leading to no answer haha. i guess i just have to wait and see what others figure out. thnx though. but btw, how does ur pedal feelnow with the 4 disks and the larger MC, same as oem? firmer than oem? or lighter than oem? thnx Quote Link to comment Share on other sites More sharing options...
240playtoy Posted August 1, 2006 Author Share Posted August 1, 2006 The pedal is rock hard. (I've also got the stainless braided flex lines). Quote Link to comment Share on other sites More sharing options...
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