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I just got my 67 out of storage and I took it for a drive. I went to stop at a light and the front wheels locked up. I limped the car home and found that the master cylinder rear resevoir was nearly empty. I guess the reason the front brakes locked up so easily was because the rear brakes wern't doing any work so all momentum was pushed to the front of the car.

As a result I've been trying to bleed the rear brakes but air is constantly being pushed through the clear inspection tube I connected to the end of the bleed nipple. Me and a friend must have pumped and cracked the bleeder a good 35 times and still no better results.

We also noticed that if we pump the brakes quickly and immediately remove the master cylinder cover, the rear resevoir fluid looks white because the fluid is entraned with so much air, almost like the fizz from a soda pop. The fluid eventually goes back to a transparent liquid like it should. The front resevoir never gets fizzy and always stays clear.

I know the fresh fluid has made it's way to the rear brakes because I could tell the difference between the old fluid and the new by it's color change.

Does this sound like the master cylinder is shot? It looks original to the car so it could be worn.

Does this sound familiar to any one?
 

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Oh now thats odd. Sounds like the system is pulling air in on the return stroke, like a leak. But you would be talking about fluid leaks everywhere if that was the case. Hydraulic pressure overcomes a simple air leak.

Almost sounds like a guy that doesnt know how to bleed the brakes, sucking air at the bleeder. But thats not the case, you guys know what you are doing. So, air is being pulled in when you bleed the system.

When all the bleeders are tightened down and you press on the pedal you dont have ANY brake fluid leaks??

Ok... It sounds like you know how to bleed the brakes. And the hydraulic system it tight, no fluid leaks??

It sounds like you are pulling air in while bleeding. If you have the bleeder tube at the nipple, make sure its a tight fit, not able to suck air while bleeding. But that is only a problem with one person bleeding systems, Cause on a two person bleed you only crack the bleeder while the pedal is depressed, right?

On a hydraulic brake system you cant be leaking air in, fluid always leaks out. Interesting.. JR
 

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How long was it in storage? Dot3 doesn't evaporate; did you notice any puddles?

It sounds like there is still air in the master cylinder. One way to get rid of it is to press the pedal very slowly to the floor, then release. Do it with the cover off, and you should see little bubbles rise up. You can also do the pump and crack technique at the master cylinder, see if that lets any air out. Makes a bit of a mess, so have a big towel under the master cylinder.

I am mostly concerned with where the fluid went in the first place. Pull the rear drums and check the servos. They should be absolutely dry. If not, they are leaking, replace them.
 

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You may have a leak at the master cyl.. you might want to pull it off the fire wall. I've also had them leak thru to inside of the firewall and the jute insulation hid it from view.
 

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that last post reminded me of something.. I have heard of master cylinders leaking out the rear, into the vacuum booster.

ALA KAZAM! fluid dissapears!
 
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