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Discussion Starter · #1 · (Edited)
I just got my 72 GT running (still needs work) and not driving it yet.

Keep in mind that this car has not been driven since 89......

Basically I have no brake pressure in front (Disc brakes), and bearly in the rear, but can not stop the car and can bearly stop the car using the emergency brakes.

I have the dual master cylinder; the break fluid did drain out for the rear brakes.

I had a friend pump the brakes and the front disc brakes did not move and no fluid came out the bleeder. Checking the rear right, only the left piston is moving (fluid flowing ok and was able to bleed).

I do understand I have to first make sure that there is no air in the master cylinder.

1) How do you properly bleed the master cyclinder and remove any air and can I do this myself without a assistance.

Does this sound like I need to replace the whole braking system or How can I get my brakes working so I can use it?
 

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Qwick;
By the time you go through replacing hoses and such to get fluid out to the calipers and such, you might just as well go ahead and redo the whole brake system. This entails:
rebuild/replace m/c
replace the 3 rubber brake lines
rebuild/replace calipers
rebuild/replace wheels cylinders
new front pads
new rear shoes
The bleeding can be done by yourself with a device called a "1-man bleeder" There are several types of these. This would also be a good time to consider going to the larger 75 brakes. But, all in all, you don't want to take a chance with you life, so do the brakes right!;)
 

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Qwick, usually what happens is the rubber hoses deteriorate inside and act like one-way check valves in either direction of flow. This means the brakes will work one way and not release or they won't work at all. There are as BQS4 says 3 hoses, two for the front discs and one for the rear brakes. Get hold of OGTS and get the parts you need for a complete overhaul of the brakes. There is no need to have the car run, get it on the road and then worry about stopping it. Get it to stop first, then get it to go. You can bleed the master cylinder with a kit that consists of two plastic plugs that screw into the master cylinder, and a hose is attached to each plug and routed back into the master cylinder into the brake fluid. This kit usually comes with a new master cylinder. Slowly push the MC piston all the way in and watch for air bubbles coming out of the hoses. Continue cycling the piston until only fluid comes out the hoses. This is called bench bleeding and should be done prior to installing any master cylinder.

Ron
 

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Life Long Opeler
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Mine sat for a long time and did the same thing. I replaced the three hoses and now they work like a charm. If you are budget concious, go with the hoses first. If it still sint working right, then go to the m/c and do the system.
 

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Discussion Starter · #5 ·
Qwick said:
I had a friend pump the brakes and the front disc brakes did not move and no fluid came out the bleeder.
I meant to say the disc brakes didn't move.....
 

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Opel Junkie
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doing the hoses is certainly a good thing to do. however, my experience shows that if the car sat for a long time, the calipers and wheel cylinders will probably be stuck.

i repaired mine by rebuilding the calipers with a kit from ogts, and did the same on the rear brake cylinders. all 4 were found to be stuck, and were difficult to get apart. while i had them apart i found that there was corrosion in all of the cylinders, and a light cleaning with scotch brite cleaned them right up. after reassembly and installation, i drained all of the brake fluid out and replaced it with new, bled the brakes and functionally checked all 4 wheels. everything now works fine.

good luck, and make that thing stop!!
 

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Just found out that my brakes stopped working, the fluid resivour is empty, I filled it up with dot 3 and I'll bleed the brakes but I saw no fluid any where by connections or hoses. where did the fluid go?
 

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If there were no noticeable wet spots around either the calipers or the rear wheel cylinders, then the next best guess is the brake fluid went out the exhuast pipe. The route would be from the MC into the Booster cannister, then into the intake manifold via the hose from the vacuum booster, into the head and out the exhaust. Sorry, but that's the next best guess. :(
 

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BQS4 said:
Qwick;
By the time you go through replacing hoses and such to get fluid out to the calipers and such, you might just as well go ahead and redo the whole brake system. This entails:
rebuild/replace m/c
replace the 3 rubber brake lines
rebuild/replace calipers
rebuild/replace wheels cylinders
new front pads
new rear shoes
The bleeding can be done by yourself with a device called a "1-man bleeder" There are several types of these. This would also be a good time to consider going to the larger 75 brakes. But, all in all, you don't want to take a chance with you life, so do the brakes right!;)
I agree wholeheartly with Gene on this, and have done everything he has listed. I bought a rebuilt Master Cylinder from Parts America the other week for $44 + $10 S&H. The "1-man bleeder" is available from Russell called Speedbleeders. Russell Performance Products 3957 (7mm x 1.0 x 34mm) http://www.speedbleeder.com Also Napa sells them 2 to a card $15/ card, Part nos 675-1572. I haven't replaced the MC yet it's on the "to do list" now that the engine's out of the car and easier to get to. It's great to get going, but you've got to stop, sometime. HTH. Jarrell
 

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A friend of mine helped me bleed the brakes, and the pedal is more solid than ever. I'll have to see if I can keep fluid in the reservoir after I drive it a little bit.
 
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