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DeeVeeEight
01-14-2010, 10:54 PM
The brake pedal on my '79 was low so I dropped it off at the shop for a fix. The rear reservoir on the MC was only 1/2 full so the guys put pressure on the pedal and left it overnight to see if a leak would show itself. Next day comes and the pedal is still hard, no leaks anywhere. Where did the fluid from the rear MC reservoir go?:huh:

big2bird
01-15-2010, 02:22 AM
The brake pedal on my '79 was low so I dropped it off at the shop for a fix. The rear reservoir on the MC was only 1/2 full so the guys put pressure on the pedal and left it overnight to see if a leak would show itself. Next day comes and the pedal is still hard, no leaks anywhere. Where did the fluid from the rear MC reservoir go?:huh:

To the worn out pads?

SmokinBBC
01-15-2010, 02:35 AM
It wasn't there to begin with or you have a leak that they didn't find or it is seeping out slowly over time through a pin hole in the line or the calipers.

Twin_Turbo
01-15-2010, 07:57 AM
Symptoms of internally leaking master cilinder

JPhil
01-16-2010, 04:02 PM
Symptoms of internally leaking master cilinder


....into the vacuum booster.

DeeVeeEight
01-16-2010, 04:15 PM
Got the car back, pedal is nice and firm, the MC was pulled to check rear seals - nothing there to report. No leaks in the lines or at the rear calipers. Could this be an example of air getting in to the system via the caliper seals? And it still leaves the mystery of where did the fluid go? :confused:

:drink:

PS - it's nice today - a road test is next.

mrvette
01-16-2010, 04:58 PM
Check that warning light valve on the frame below the m/cyl.....mine insisted on leaking enough I got pissed and pulled it outta there entirely....I don't need a warning light to say my brakes are bad.....

:crap::gurney:

JeffP1167
01-17-2010, 04:50 PM
Got the car back, pedal is nice and firm, the MC was pulled to check rear seals - nothing there to report. No leaks in the lines or at the rear calipers. Could this be an example of air getting in to the system via the caliper seals? And it still leaves the mystery of where did the fluid go? :confused:

:drink:

PS - it's nice today - a road test is next.

My 82 did this some years back. Leaking piston seal on the rear caliper you don't notice a leak because the usually drip on the rotor and the braking action burns the fluid away. Being it's your rear portion of the resevoir thats low I think thats the resevoir for the front brakes if I'm not mistaken. Also look for leaking where the lines bolt to the calipers maybe seeping out of that brass washer. Also check all the lines to make sure they are tight, the fluid just don't evaporate out of the resevoir :sos: