coldy13

They seemed to be working fine this monring, but when I left school they we're almost not there. The pedal woud go straight to the floor with almost no resistance, and would barely slow the car down, so I had to drive home using that and the e-brake. I checked all the lines, no leaks. All the brake fluid is gone out of the resivior(I just filled it 3 days ago). I think it might be leaking out of where the master cylinder connects to the vacuume booster. I can't really tell though, I'll have to get a better look at it when I get home from work. Any other areas I should check and see if it's leaking?

-Matt

Rotor13B

Check the carpet near the clutch pedal. Make sure you lift it up, I bet you'll find your leak.

Forseti

Seems like the leak is fairly significant.

One thing you could do is top up the master cylinder. Then get in the car and pump the brake pedal to feed pressure to the brakes.

Then get out and inspect underneath the car for any dripping or leaking of brake fluid.

A bit messy, but one way you may be able to get an idea where the source is.

F-

error402

Hehehhehe....this just happened to me last weekend. Sounds exactly what my symptoms were. I replaced the master cylinder and all was well.

-Error402

Forseti

Seems like the leak is fairly significant.

One thing you could do is top up the master cylinder. Then get in the car and pump the brake pedal to feed pressure to the brakes.

Then get out and inspect underneath the car for any dripping or leaking of brake fluid.

A bit messy, but one way you may be able to get an idea where the source is.

F-

coldy13

Well, f*ck. Master cylinder was bad and since I have no ride, my dad picked up a rebuilt one from NAPA. F*cking POS doesn't work either. Bench bled the cylinder, put it on the car, bled rear brakes. Went to bleed the front, and theres NO pressure. Brakes fully depressed, and I can still turn the front rotors by hand. Tryed to bleed them for a while, still nothing. Disconnected the lines that go to the front brakes right off the cylinder, press brakes, nothing comes out . POS rebuilt part...I told him to get a new one since I'm paying for it anyway....I gotta pick up my girl to go out tonight and I have no car. F*CK.

-Matt

inittab

bleeding the front brakes is a two person job. Your brake pedal assistant needs to push the pedal to the floor while you open the valve. Do not lift up on the pedal untill you first close the valve.

this is how it goes:

open valve, push pedal, close valve, lift pedal, repeat. It will take a dozen times of doing this before you'll get fluid to flow out. Do the passenger side first.

I bet this will cure your problem.

Forseti

Heh yeah that's if your bleed valves aren't old and seized like mine are..

Yeah definitely get someone to assist you in bleeding.

Funny I never had too much trouble getting the fluid to come out once I pressurized the system with the pedal.

F-

White84SE

Hmm.. something that may have happened... since you mentioned you drove it with non-functional brakes, the emergency switch that shuts off either the front or rear lines in case the other blows out may have been tripped. My experience with NAPA parts has actually been very good. Read the manual and try to reset the switch, then see if your fronts start working again..

--Danny

Rx7carl

Huh???? WTF are you talking about? Its a dual system. Front and rear are totally independent.

White84SE

So are Datsun 280Z's, almost all Triumphs.. but there's a switch called an emergency pressure differential valve or something of that nature.. it senses when one system, front or rear experiences a sudden loss of pressure compatred to the other, and shuts it off. For example, you're driving down the road, you hit the brakes and a front line blows out. The switch sees this and shuts off the front lines, transferring all braking power to the rears. I'm looking at the factory manual right now, and it appears I was wrong.. seems RX-7's don't have these.. oh well, disregard my comment...

--Danny

coldy13

I know how to bleed brakes, my dad was doing the pedal while I was opening and closing the valve. Turns out that the remanufactured master cylinder wasn't bad, it just has some kind of gas-lock. I took it off again and started bench bleeding it- temp. rubber lines on all 3 holes which are running back to the resivoir, and push in the cylinder using a small wooden rod. It took about 1/2 hour to get it to flow out of all 3 holes. For some reason it just didn't want to get the fluid flowing through the ones that go to the front brakes. Put it on, bled the rest of the brake system, and now it works great. Much firmer pedal than I'm used to, of course I was using a leaking master cylinder before, so I really hope it would be better.

error402

Good to hear everything worked out for you!

-Error402

Strider

Anyone every try Russel Speed Bleeders? Do they make one that works with the RX-7? I have a set for my motorcycle, and they are great, especially when I change my fluid once per year (Hey, the book calls for it, and brakes on a motorcycle are so much more important than the motor!). Anyway, these replace the stock bleeder bolt, and basically have a ball check valve built in them, so you can do your initial bleeding with the valve open and keep pumping. Once the majority of the air is bled out, then do your final bleeds in the standard way. They are a huge timesaver.

Felix Wankel

Yeah they make those.

I usually use a Mityvac because I can't find anyone to pump the pedal for me.