Guest tony78_280z Posted April 24, 2006 Share Posted April 24, 2006 I've always had brake problems with this damn thing. I've replaced both front calipers, both rear pistons, the Master Cylinder and all four rubber lines, and most of the metal ones too. But my brakes are still squishy and I can't figure out my problem. At First I just thought I wasn't bleeding the brakes correctly. But I am begining to suspect my Master Cylinder is at fault. Symptoms: Squichy Brakes The other day, I noticed the front resevoir lower than it should have been. Is it going from the front circuit to the rear? I Don't know. I have only caught it doing this once, but I'll keep my eyes on it. When I push on the brakes the master cylinder makes a squish noise similar to that noise your eyelid makes if you lift it off of your eyeball and squeeze out the air. It will brake if I floor it or pump the brakes. What other ways are there to test this Master Cylinder before I mail it back to VB and demand another one! Thanks Quote Link to comment Share on other sites More sharing options...
Clifton Posted April 24, 2006 Share Posted April 24, 2006 Two things that I know that will cause this. 1. Did you bench bleed the MC? If not you can do it on the car and just return the fluid back into the resevoir. 2. Reaction disk dropped down into the vacuum booster when MC was out. Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted April 24, 2006 Share Posted April 24, 2006 there have been many threads on this subject. Seems defective MCs are not that uncommon. But before you go tearing it out and replacing it, try adjusting the rear brake shoes. Clifton's suggestion to bleed the master is a good one as well if you never did it. Quote Link to comment Share on other sites More sharing options...
olie05 Posted April 24, 2006 Share Posted April 24, 2006 Tony, I had the same problem! Link to my post on the problem link to the first update, when I started replacing parts link to second update, when I replaced MC link to understanding the brake MC BTW I did get a bad MC from the parts store, so it is not uncommon for something like that to happen. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted April 25, 2006 Share Posted April 25, 2006 1. Did you bench bleed the MC? If not you can do it on the car and just return the fluid back into the resevoir. 2. Reaction disk dropped down into the vacuum booster when MC was out. I bench bled it before installing it. And it worked fine for a bit. After replacing both rear pistons I bled the entire system starting with the MC. I've bled the system 4 times with no improvement. What is a reaction disk? Seeing as how the MC worked fine for awhile after installation, I'd say this is not the case. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 25, 2006 Share Posted April 25, 2006 If you've got fluid moving from one reservoir to another you need a new master. It's as simple as that. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted April 26, 2006 Share Posted April 26, 2006 Checked it again, the front is low. I don't know if If it is moving from one to the other as the other is always full, I can't find a leak anywhere though. You'd think if it was a leak It'd eventualy empty, and probably pretty quick too. I got this latest MC from Black Dragon Auto when they were called BV or VB or whatever. They offer 180 day return policy, and guess what!! Looks like I'm forking over $$ for another new one. Anyone recomend a seller/brand name? Please! Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted April 26, 2006 Share Posted April 26, 2006 Anyone recomend a seller/brand name? Please! OEM - Nissan call courtesy, they still have oem master cylinders and they come with the cups and caps and the whole bit... nice Did you try adjusting your rears? I bled and bled but until I adjusted the rears out some, the pedal would not get hard Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 26, 2006 Share Posted April 26, 2006 Don't forget to check the classifieds! Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted April 27, 2006 Share Posted April 27, 2006 What do you mean by this? Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted April 27, 2006 Share Posted April 27, 2006 What do you mean by this? You're still using the stock rear drum brakes right? If so here is the deal... With the drum off, at the bottom, there is a threaded collar between the brake shoes. On this threaded collar there is a toothed wheel (sort of looks like a multi point star) that when turned, threads the collar out. Doing so expands the brake shoes. (pushes them further apart) In the backing plate, there is a slot where a 'brake spoon' or plain flat screwdriver can be stuck through and used to turn the toothed wheel, thus giving you the ability to adjust the assembled brakes with the drum on. There is also a mechanism to do this automatically (when you apply the e-brake, I think) to accomidate for brake shoe wear. If you adjust them down to where the drum will go on, they won't be out far enough. You must put the drum on and then adjust them through the little slot until they begin to drag. I really suck at trying to explain things in writing, so if you don't understand what I'm saying, or need more help, post again. I think I have a picture at home with the drums off that will show what I mean or if anyone else wants to try to explain it better... go ahead Quote Link to comment Share on other sites More sharing options...
Darrel Posted April 27, 2006 Share Posted April 27, 2006 Do the front calipers have the bleed screws at the top? Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted April 28, 2006 Share Posted April 28, 2006 I really suck at trying to explain things in writing[/b'], so if you don't understand what I'm saying, or need more help, post again. I think I have a picture at home with the drums off that will show what I mean or if anyone else wants to try to explain it better... go ahead I hate to say it, but I agree with you. This adjuster that you describe is used to release pressure to remove the brake drums. Is it also required that I re apply this pressure. I thougth that it atomaticaly adjusted its self. Please explain further. Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted April 28, 2006 Share Posted April 28, 2006 I hate to say it, but I agree with you. sorry This adjuster that you describe is used to release pressure to remove the brake drums. I've never considered it to be specifically for that purpose but I suppose you could use it to do so Is it also required that I re apply this pressure That is how I understand it, yes. I thougth that it atomaticaly adjusted its self. My understanding is that the automatic adjustment is made to slowly, over time as the shoes wear, incrementally take up the slack and keep the brakes properly adjusted. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 28, 2006 Share Posted April 28, 2006 Brake adjusters are not there so that you can remove drums. The drums shouldn't be so tight that you can't remove them without loosening the adjuster. That said, a lot of cars are neglected, and the shoes go metal to metal, then you HAVE to adjust the shoes back because the groove that they grind into the drum prevents it's removal. The adjusters are really there to tighten the shoes against the drum. The shoes should be lightly dragging on the drum when everything is correctly adjusted. mom'sZ is right that having the drums poorly adjusted will cause a long pedal throw. Still, if the level in one of the reservoirs is going down and there isn't a leak then your master is bad. If you aren't sure about this, draw a line on the master to mark the current location and check it again in a couple days. Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted April 28, 2006 Share Posted April 28, 2006 OK... it took me forever to find this damn post, but I finally did! Check out bjhines post (#6) about how to adjust the rear drums using the parking brake. http://forums.hybridz.org/showthread.php?t=107051&highlight=e-brake Also, here is a thread that a guy was having problems with his rear drums loosing adjustment. In this thread Wayne Karnes explains in post number 2 how the automatic adjuster work and how to fix em. http://forums.hybridz.org/showthread.php?t=92063&highlight=brake from reading a few of Waynes earlier posts, he apparently has intimate knowledge of this because he had a problem with them not working which caused one wheel to lock up. the search function is me buddy Quote Link to comment Share on other sites More sharing options...
Nismo280zEd Posted April 29, 2006 Share Posted April 29, 2006 You should try what i did tonight, take the line that goes to the brake booster, stuff a sharpie in it. Then go drive the car. Mine stops better without the booster. -Ed Quote Link to comment Share on other sites More sharing options...
Nismo280zEd Posted April 30, 2006 Share Posted April 30, 2006 all nissans with drums asjust this way... you use the ebrake to tighten it. Quote Link to comment Share on other sites More sharing options...
DaleMX Posted April 30, 2006 Share Posted April 30, 2006 My spongy brake problem was the reaction disk. I bleed the snot out of it, replaced the MC twice to no avail. Then I bought a new booster and made sure the reaction disk stayed in place during the install and the problem was solved. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted May 1, 2006 Share Posted May 1, 2006 In Bjhines wordsok.... something is not assembled right... OR you did not understand the function of the automatic adjuster lever.... If your E-brake cables are in good order... then the rear brakes will adjust themselves with repeated pulls of the E-brake handle.... during assembly I usually leave the adjuster in its "smallest" setting... Once I have everything assembled and the wheels are torqued to specs. I repeatedly pull the E-brake handle until I can no longer hear a clicking noise from rear brakes.... this is PERFECT preloading. There is no other way to properly adjust the rear brakes... period. Will do this tomarrow. Seeing as how my E-Brake doesn't work, this may be suspect. What is a reaction disk, and how is one tested. As far as I know my booster is working well. I will update tomarrow Thanks Quote Link to comment Share on other sites More sharing options...
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