xman

Having problems with my !#$%!^@$&^ brakes!!!! I have 4wheel disc, and here's the symptoms. When I initially step on the brakes they go right to the floor. If I release them and step on them again they work normally until I release them. I have bled all of the calipers in the proper sequence (on more than one occasion), and they are still the the same. Thought it might be my master cylinder, but there doesn't seem to be any fluid leaks around it. My rear calipers might also be in need replacement, as I could not seat the piston (it too hard to move without a tool). I normally just use some pliers, but it was too difficult on one of them. Could my problems be the calipers, or perhaps the booster? I know only the basics when it comes to brakes, and just can't figure this one out. Hopefully someone can help me before I plow into the next car that stops short.

vipernicus42

iTrader: (4)

So you're not leaking fluid anywhere, your fluid level does not go down, and you've bled the system of air?

Hmm... my guess would be then that it's the booster. Depending on where the stuck caliper is, it *might* have something to do with it, but I'm also not a brake expert... I would start with the booster, if that doesn't solve it, you probably needed one anyway because after all, our cars *are* 20 years old!

Jon

djmickyg

im going with air in the lines also..

how are you bleeding them? have u got one of the many fancy tools that close off the lines when u take ur foot off the acc when ur pumping it. or got a mate to open and close it as ur doing it? other wise it will suck air right back in..


and when u blead it do u leat the master cylinder go dry? if so u might have to blead this as there might be air traped in there..

also check booster vacume line for air leaks.. i dout its this but its worth a cheak.

Pittdp

are you bleeding the brakes or completely evacuating the system. You will need to get all the fluid out to make sure there is no air, besides is good to put in all new fluid every brake job to get ride of the out fluid in the system since it can become corrosive over time. my brakes feel much more responsive since I evauated the entire system and pull all new fluid in.
P.S. I had change out the bake drums and the passenger side one is getting really hot, I think it is just braking in. there seamed to be alot of air in the back when flushing the system and I do not think the bake brakes were working that well untill now.

J Oliver

IT IS YOUR MASTER CYL.!
The thing bolted to the brake booster with all the 4 brake lines going to it. Go to Mazda and buy a rebuild kit or spend a bit more and just get the whole master cyl remember to take your old one in for a core or it will cost you even more. It took me all of an hour to do mine so it is not a big job. I drove my car 4 two weeks with my pedal falling to the floor, DONT DO THIS!! Please do not procrastinate on this, we dont need to lose another 1st gen owner and or car.
Now hurry go fixit.

Pittdp

sounds like good advise to me. by the way how long does the master cyl usually last anyway?, I dont think I have ever changed mine and I am going on 229k, and have had the car since 113k.

inittab

What J Oliver said! It's your master cylinder.


This all depends on how often the fluid is changed and a little luck. If the fluid is never changed there will be water in it that'll cause corrosion and cause it to fail sooner. My guess is that cars in dryer climates have master cylinders that last longer.

--Bob

Pittdp

I just relized that I need to flush the entire system. the old brake fluid was orangish brown, no wonder my brakes seemed to fade if I got on the brake hard.

xman

Bleed the system using a one-man brake bleeding kit. The fluid in the back was pretty dark and grungy looking. Probably caused corrosion in the rear calipers. Will no doubt have to replace them.
My guess on the problem was also the master cylinder, but wanted to make sure before I spend the cash to pick one up. Don't think it is the brake booster as I can't hear/see any vacuum leaks around it. Any idea on how to check this properly? Also any idea (roughly) what a master-cylinder goes for? Oh yeah, one more thing. Is there an easy way to remove the parking brake cables? It takes me more time to remove these than bleeding the system/ changing the pads, etc. You'd think Mazda would have made this a little easier. Am I just a bone-head doing it wrong?!?...... if the answer is yes, please just humor me, remember I have to take another crack at those brakes today!!!!
P.S. if I crash hopefully I'll take a Honda with me!

Pittdp

HOW MUCH DO THE KITS GO FOR?

specRX7_22

there no reason to rebuild a master cylinder.... you can get remanufactured or rebuilt at auto zone for about $20. we had a weird problem with the one we received tho. the resevoir tank didnt fit correctly into the master cyl. and auto zone was like "oh just press it in it will go" and it obviously wasnt going, so we took it there and sure enough... "hmm your right, it doesnt fit". so we fitted another one right there and it was fine.

the particular problem that we were trying to solve by buying this part was soft pedal. my dad would have to pump it up then it would be fine. turned out to be the booster.

xman

I live in CANADA, and got the kit for under $5.00CDN at a local parts store. They're pretty handy cause they have a magnet on the bottle so you can hang it anywhere in your wheel-well. You can also get a hand-held vacuum-type that you can use for all sorts of automotive stuff. I got one of those too for about $60.00CDN (so about $2.50USD!!!).
By the way, does anyone know how to remove the e-brake cables? I'm thinking there's an easier way than mine which is not easy at all!!!! (i.e. curse, hammer, pry, curse some more.....voila, 1hr later and it's off!!! Now for the other side)

Wankelguy

Sounds like the brake fluid recirculating in the master cylinder to me. I've got the same thing going on with my car, though to a lesser extent. I like to rebuild them when possible as I am a cheapskate of epic proportions.
But if you can find one for $20 as mentioned, that is certainly the way to go.

Forseti

To easily disconnect the e-brake cable...release the handle inside...and then use two vise grips to clamps the old bolts and twist them. Sometimes, it will come off without having to loosen the nuts.

Make sure when you replace it there's no tension on the cable with the e-brake released.

Are you 100% sure you've bled the system properly and in the correct order ( master cyl, rear passenger, drivers rear, passenger front, drivers front)?

If the rear pistons don't move freely...time to get new calipers...they can be found used at many junkyards for a reasonable price., (www.car-part.com)

<F>

Phiber Optik

iTrader: (2)

I had that same problem after I replaced my leaking rear caliper, I bled all the lines over and over again with no progress, so I took the car to the local Midas and got them to pressure bleed all the brakes, and it worked

xman

Haven't bled the mastercylinder as mine does not have a valve on it. Bled everything else though in the right sequence. Will probably be getting new calipers for the rear as I don't think that they're easy to rebuild, and you can never trust the ones you get at the wreckers. Would actually like to find a GSL-SE and change everything over to the larger discs, etc. Here's to wishfull thinking!!! Thanks for the info!