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Discussion Starter #1
Hadn't driven my '69 camaro since September - had it stored away for the winter, but needed to move it to another location today. Well, out of my driveway, noticed right away I had almost no brakes. Pedal almost to the floor.
I limped my way to the new location. Checked brake fluid level - fine. Checked vacuum hose to he booster - fine.
I'm far from a mechanic, but before I bring it in to a brake shop - any simple things I can check for first?

Thanks

Gary
 

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I'm guessing it is the Master Cylinder that is shot, does not take much for these to fail. And assuming no fluid is draining from a leaking wheel cylinder.
 

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I'd check for leaks everywere. Pull the drums and check for leaks. Look for leaks where the MC connects to the booster and also take a look for leaks at the hold back valve, but if the fluid level was good in both compartments of the MC you probably don't have a leak. It could be that that MC has just gone bad as our colleague has already suggested. Does seem a bit strange that the brakes don't work after the car sat for only 6 months or so. I'm assuming that your rear brake shoes are adjusted correctly.
 

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Probably too late to ask if any wet spots inside the wheel or tires. That should tell you about leaks.
As for the car being set up for winter, the internal plunger seals could have collasped, thus internal m/c bypassing.
 

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Discussion Starter #5
Thanks for the replies.
There were no apparent leaks, although I didn't actually check inside and around the wheels - just nothing on the garage floor. Both compartments in the reservoir were full, and so I just assumed no leaks.
I'm just going to take it in to the shop from here. Thanks again for the ideas.
 

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Quote: "Checked brake fluid level - fine."

While this doesn't completely rule out a leaking wheel cyl, it is strong evidence that the master cyl is simply "bypassing", meaning, you push the brake down and the fluid bypasses the seals in the master. Happens with non use. If the fluid had gone through a leaking wheel cylinder, the level in the master would be low.

Try this. Start the car. Push brake pedal really fast and hard. See if it holds. If it does, try pushing again, this time with light pressure. If it slowly goes down to the floor, then you need a new MC.

You PROBABLY need a new MC even if it doesn't hold on that first hard fast push. But the above test would confirm.

Look for any leaks at the wheel cylinders by pumping the master a few times, then look at the bottom of the drums from under the car. That is where the fluid would collect. You can pull a wheel and drum if you want, but if it is leaking badly enough for the pedal to go to the floor, the level in the master would be going down, and the fluid would be collecting at the bottom of the brake drum.
 

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The timing of your problem could be coincidental. Over time with use the MC piston travels back and forth over a somewhat fixed range of motion. This can build up a slight ridge the end of the piston stroke. If for some reason the piston travels past this ridge it can damage the seals and start leaking or not functioning correctly. This is why if one is going to use the pedal to bleed brakes the manual way on a used MC as opposed to a brand new one, it is a good idea to first determine the range of normal motion and put a block under the brake pedal so when the brake pedal is pushed for bleeding a well used MC it does not go past its normal maximum range of motion and certainly not to the floor thereby possibly damaging the seals in an otherwise good MC.
 
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