Brakes

[silvergsx623]

Ive had a problem with my brake system.:aigo:

Before:
The pedal would sink in 1/2 when i touched it and would stick down. I would have to pull it up by hand or it would brake the car automatically.

After:
So i replaced the master Cyl with a rebuilt one. I bled the Cyl, attached the 2 brake lines then bled the brakes. Finally got Working correctly the brakes were very responsive and felt great. After the car set for a week, the brakes started doing the same thing as before. made me think i had a leak somewhere.

Post Problem:
The pedal is hard to mash at first, but it will sink in and its spongy feeling. I bled the brakes again and it helped with the spongy feeling but the brake pedal will not return to the top with out me pulling it up by hand.

Out of ideas::1zhelp:

Anyone have ideas? Thanks

 

[kabanimk3supra]

have you checked the brake lines?

 

[suprahooked]

I am thinking you have a bad slave.
Edit Duh i was thinking clutch.

 

[silvergsx623]

have you checked the brake lines?

what do you mean?

Yes the lines work, they don't leak fluid out. My res. is full after driving it around for about 30 mins. Its hard to drive with sticky brakes.

 

[silvergsx623]

I am thinking you have a bad slave.

I didn't know there was a brake slave cyl?:aigo: part #?

Thanks guys

 

[silvergsx623]

what do you mean?

Yes the lines work, they don't leak fluid out. When i bled them plenty of fluid comes out so they are not clogged. My res. is full after driving it around for about 30 mins. Its hard to drive with sticky brakes.

also there are no drips on the ground under the car:icon_mad:

 

[mkIIIman089]

Sounds like 2 bad masters to me.

 

[silvergsx623]

Would a leaky booster cause it?

 

[silvergsx623]

Sounds like 2 bad masters to me.

Thats what i was scared of :cry:

 

[mkIIIman089]

Is there no warranty on the one you bought?

 

[silvergsx623]

I'm sure there is... i just dono where the receipt is lol

oreillys auto parts, do they store it in their computer?

 

[mkIIIman089]

Couldn't tell you. I don't ever buy parts from discount places for my own car.

 

[kabanimk3supra]

more than likely its the master...i had the same problem with my car. it was the master. the reason i pointed out the lines is that you said that you had already replaced the master......

 

[silvergsx623]

Update:

On the 3rd Master Cyl.

This one i was able to bench bleed. I got it put on tonight and spent about an hour bleeding the brakes.

When the brake pedal is mashed, you can hear a swish in the line/s around the ABS pump.
I am assuming this is air in the lines?

i went through 2 bottles of brake fluid... each time i bleed the brakes it gets a little harder to mash the pedal. (closer to normal feel)

Any ideas on how to speed the process up?

Thanks!

 

[TurboStreetCar]

wouldn't if the booster was malfunctioning it could apply vacuum at all times to the pedal making it "stick"?

 

[silvergsx623]

If i mash the brake pedal as hard as i can down, and let up on it. It will return to its normal position.

If i mash down as if i were normally braking... it does the sink in and stick down partway thing.

Booster... any info on testing it?

Thanks for your time!

 

[Poodles]

I'm sure there is... i just dono where the receipt is lol

oreillys auto parts, do they store it in their computer?

yes, it's stored in their computer


you can get the pressure bleeders (it's a pump with a resivour to put the new brake fluid in and it moutns to the master) for your brakes that will force the old fluid out and replace it with new all the way through

 

[OneJArpus]

Check the booster, lines, calipers, pads

 

[3p141592654]

Remove and plug the vac line to the booster. Then repeat your experiments. Be aware that if you drive with the vac line off, the effort required to stop the car will be way higher than normal, so limit your testing to the driveway.

 

[Adjuster]

I use my power bleeder. (Takes a compressed air source, and it sucks all the oil fluid out of the system at the calipers.)

They are about 75.00 last time I bought one. (Has a clear plastic container with a trigger handle on the top that is part of the lid to the container. These work best.)

Then there is the mittyvac. They work OK, but you can do two things with them. You can suck out the oil fluid, or you can reverse it, and force new fluid into the calipers, and then suck out what's bad out of your master cyc. res.

Personally, I like my setup better. To bleed the ABS faster, use the bleed valves on the ABS unit... They work, but you will need a long clear tube of the right ID, and a small clear cup of brake fluid.
Loosen the bleeder for the rear brakes first. (The MA70 is a 3 channel ABS system, one for the rear brakes, and two for the Rt. and Lt. front brakes.)

With an inch of fluid in the cup. put the hose on the rear bleeder. Then loosen it. (box end wrench works great here.) Just a 1/4 turn or so is fine. This helps if you have someone to push the brake down...

Ok, here is what I'v found works best. Have someone push the brake slowly 3 times, then HOLD their foot down hard.
Crack open the fitting, and watch the fluid/bubbles come out.
Close the fitting.
Now have your friend slowly push down the brake 3 times, and hold it again.'
Crack open the fitting, and repeat untill you no longer see bubbles come out.

Repeat at the other two ABS fittings.
Repeat at the rear brakes first, then fronts.

Make sure your res. has the right amount of fluid in it. Not too much, and not too little.

As your doing this, your friend is going to notice that the brake will become quite firm. This is how it's supposed to be!

Have fun, and don't drive around on brakes with air in the lines

With my power bleeder, you just hook it up to the fitting, crack it open and let it suck out fluid and air. All you need to do is add fluid to the MC as it is being sucked out by the power bleeder... This makes changing your fluid so easy, it's not even funny. You can even do it with the wheels on the car if your careful.