theloudroom

Crap!

My car is leaking brake fuild and I wanted to autox tomorrow!

The fluid seems to be leaking out somewhere around my master cylinder, but I don't have the symptoms of a bad master cylinder (pedal sinks slowly to the floor).

My car is very clean and rust free under the hood, so I find it hard to believe it would be a corroded brake line.

Anybody have some ideas? I lost 1/4 of the reservoir of fluid last night.

I can stand on the brakes, and it it holds pressure. It also doesn't spray fuild everywhere when I do so. The brakes seem to work just fine.

I need to get this fixed tonight, or I won't be able to try autox 'till next year

Icemark

The most common spot is the bushings between the brake master cyl and the brake fluid reservoir.

You can get both the bushings at any Mazda dealer for under $10

If you spray the master cyl down with brake cleaner, it should be pretty easy to see where it is leaking.

eoph

my brakes are leaking, prolly need some new brake lines, but if my car is not moving everytime i hit and let go of the brake it gets firmer, is this a problem or normal?????

slow87turbo

thats normal its your brake booster loosing vacume. no biggie. if it were to get softer then you woold have a problem.



ej

theloudroom

Thanks, that's what the guy at Pep Boys thought too.

I bought some gasket sealer that says it will stand up to brake fluid and I'm going to try that.

My plan is to suck all the fluid out, take the reservoir out (it just lifts out right?), and then put some of this gasket sealer on those bushings.


Now I get to repaint everything underneath that spot.

theloudroom

Update:

A nearby Mazda dealership had them.

$15 for the pair.

Not cheap, for two little pieces of rubber, but cheap enough for anything that's going to make this problem go away.

theloudroom

DAMN!

Still leaking. I bruised me hands pushing that reservoir back in but still I don't think I got it in far enough.

So yesterday I went out and bought some 3" u-bolts to crank it down with. I cranked it down and then took them off. This morning my brake light was on again.

I filled it up and put those bolts on again, clamping it down. I think I'm going to try some of that gasket sealer on it, if it ever warms up enough for me to apply it.

I'm also going to get some brake cleaner, and try to make absolutely sure that's where it's leaking from.

theloudroom

Damn!

Still leaking. I haven't messed with the gasket sealer stuff yet because I have a fear of it getting into my brake lines.

I think I'm just going to replace the mater cylinder, and install a proportioning valve and some ss brake lines, while I'm at it.

Nopi.com has one here for $80, but it doesn't look stock. Do anyone know anything about it?
http://www.nopionline.com/index.cfm?...20Cyl&vaffid=0

Nopi also lists two stainless brake line kits:
http://www.nopionline.com/index.cfm?...20Kit&vaffid=0
Does anybody know which one I need ('86 GXL)?

Nopi doesn't seem to have any proportioning valves though. Anybody know where I should look for a good product at a good price?

I suppose right now I'd be looking at one of these two:
http://store.summitracing.com/partde...rt=SUM%2DG3905
http://store.summitracing.com/partde...L%2D260%2D2220

My back wheels are locking up before my front, so I should install this on the back brakes?
Should this replace the stock "proportiong bypass valve"?
I'm guessing yes.

Looks like summit has a cheaper brake line kit too.
RUS-685600
Does anybody have this? It's $90 instead of $115.

Anyone have any suggestions?

eoph

rx7's have huge brake bias to the rear so it seems comon

Icemark

The corksport SS brake lines are already plastic coated for $89, so you don't have to worry about doing it yourself. I don't think that the Nopi lines are.

I would fix the exisiting system, before spending the money and adding the proportioning valve.

theloudroom

Good suggestion about the corksport lines.

I was figuring I'd do the proportioning valve and lines now since I'll have to bleed the whole system for each of those tasks. I'm going to have to drive 1 1/2 hrs to use a decent garage.

Maybe I'll just do the proportiong valve and the master cylinder now. That would mean I'll have replaced everything but the lines in the area where it's leaking.

Icemark

You may not need the proportioning valve if the leaks and brake lines are fixed.

theloudroom

True. Can it hurt if I didn't need it?

I noticed that according to the FSM, the stock valve isn't linear.

theloudroom

I was looking around for the leak, and I think I may have found it.

It seems like brake fluid is leaking out the back of the master cylinder. I can feel brake fluid on the bottom of the booster, and inside the car by the pedal as well.

Icemark

Yep, that is a bad thing... replace the brake master cyl (don't try and rebuild it unless you have the proper hones)

theloudroom

Thanks. Master cylinder is on order from Nopi.

theloudroom

Conclusion (for anyone who reads this in the future).

Nopi canceled my order for the master cylinder. Advance Auto Parts got me one overnight.

I replaced the master cylinder and added an adjustable proportioning valve while I was in there.

No more leak.

DocMazda

cool. thanx for the encyclopedia of information!! i have a brake fluid leak right now. i dont think it is the booster as there is no leak INSIDE my car. it is just running to the outside of my car. actually, it is spurting liquid to my blower motor cover on the drivers side of the engine bay. i am thinking it is either that brake master cylinder, or it is just those seals you were talking about. I am thinking it is the seals. this is because i had brakes on my car for awhile, but just recently did it start to leak like a ****. I am thinking it is the seals, but i am (financially) preparing for it to be the master cylinder! in any case, thanks for the conclusion, and i know it is one of those two!

boosted1205

iTrader: (9)

I hope you bench bled the master cylinder before installing.