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Old 01-19-2008, 02:04 AM   #1
truckguy_69
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Brake Problem

well ive been having good brake presure for about a week after i replaced the master cylinder lid gasket and now it has no pressure till its all the way to the floor and the brake light comes on. i checked the fluid and its full to the top and the back one on the gasket is sucked up in to the lid. i poped it back to where it needs to be and had pressure for one braking and it did it again!

Last edited by truckguy_69; 01-19-2008 at 02:06 AM.
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Old 01-19-2008, 02:45 AM   #2
70rs/ss
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Re: Brake Problem

The lid gasket is to keep the fluid in and air out, if the new gasket helped brake pressure you have a bad master cylinder and the gasket band-aided it for a little while. Try a new master cylinder, or at the very least bleed the brakes staring at the pass rear, then drv rear, then pass frt, then drvs frt. if still no pressure then get a master cylinder.
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Old 01-19-2008, 02:57 AM   #3
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Re: Brake Problem

the light coming on in the inst panel indicates an imballance in the system.
You need to inspect for leaks from front to back, look at lines, connections, front and rear brake cylinders.
Look for fluid on the inside of the tires to indicate fluid leakage from the front and rear cylinders.
If no leaks are found, then bleed brakes and inspect again. Air got in the system from somewhere.

Last edited by Longhorn Man; 01-19-2008 at 02:58 AM.
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Old 01-19-2008, 07:24 AM   #4
truckguy_69
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Re: Brake Problem

well i had just got the brakes bleed a week ago and the lid gasket 3 weeks ago and im not losing any fluid and the gasket keeps getting sucked into the lid, could the lid be bad?

Last edited by truckguy_69; 01-19-2008 at 07:24 AM.
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Old 01-19-2008, 07:39 AM   #5
Sweet72
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Re: Brake Problem

sounds like it wasn't bled completely, if bleeding won't fix it the MC may be defective as was suggested already. Why did I even bother to post?
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Old 01-19-2008, 07:41 AM   #6
Old Chevy Mech
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Re: Brake Problem

Have someone lightly press the pedal with the lid off (so as not to splash the fluid) and if you see any air bubbles coming up from inside the master cyl reservoir then the master cyl is bad as stated above. Its more prevelent when releasing the pedal.

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Old 01-19-2008, 08:18 AM   #7
68gmsee
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Re: Brake Problem

I'll chime in also. I agree with all of the above responses...

If all of the air is out and there are no leaks, then you have a mc that has gone bad. They're cheap.

Be aware that even a new or rebuilt master cylinder can go give you problems if not properly bled according to instructions or if you happend to get a defective one.
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Old 01-19-2008, 09:59 AM   #8
tim21391
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Re: Brake Problem

i bought a rebuilt master cylinder for 14 bucks at autozone....so far so good...my buddy of mine works there and he said they are good master cylinders too
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