# 1967gto brake problem



## garysgoats (Nov 28, 2012)

hi I am just finishing up a total frame off on a 67 gto with power drum brakes I am having a problem with bleeding them as I can get fluid to front drums but nothing to rear I have installed all new lines booster and master cyc when I start the car the brake pedal goes down without touching it when cut off is rises back slowly when trying to bleed seems I hit rock hard about 3/4 way down do I have a bad booster or proportion valve which I didn't replace the valve or maybe a bad booster .I bench bleed master cyc before installing seemed to be ok but cant get fluid to come out of the bleeder on master cyc for the rear any help appr.


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## 05GTO (Oct 6, 2004)

Gary,

It takes time to get the fluid to the rear drums when the lines have been replaced, start at the right rear and continue the bleeding process, then go to the left rear,


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## chuckha62 (Apr 5, 2010)

You may have to use a pressure bleeder. You might also try a vacuum bleeder and start at the right rear wheel. You probably know this, but... Always bleed the corner farthest from the master cylinder first.


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## geeteeohguy (Feb 2, 2008)

What these gents said. It takes time. I would take the cap off of the master, fill it with fluid, and crack the passenger side rear bleeder. And go get a cup of coffee and read the paper. Then, come back and look at the master cylinder level and replenish as needed. Know that the power booster has zero effect on brake bleeding: it's not the same system, being vacuum actuated.


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## InjunRAIV (Aug 21, 2013)

garysgoats said:


> hi I am just finishing up a total frame off on a 67 gto with power drum brakes I am having a problem with bleeding them as I can get fluid to front drums but nothing to rear I have installed all new lines booster and master cyc when I start the car the brake pedal goes down without touching it when cut off is rises back slowly when trying to bleed seems I hit rock hard about 3/4 way down do I have a bad booster or proportion valve which I didn't replace the valve or maybe a bad booster .*I bench bleed master cyc before installing seemed to be ok but cant get fluid to come out of the bleeder on master cyc for the rear any help appr*.


Maybe it's a language issue, but are you saying you don't get any fluid out of the master cylinder? If so, you have a bad master. If not, what the other folks said...


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## geeteeohguy (Feb 2, 2008)

.....and '67 master cylinders don't have bleeders, either. You bleed it out of the outlet lines if you need didn't do it right on the bench... Not sure what a 'cyc' is.....cylinder?


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## Rukee (Feb 8, 2007)

If you got fluid coming out when you bench bleed it, and now nothing, then either the fluid level is low, or the master is bad. You should be getting fluid at the MC lines if loosened.


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## chuckha62 (Apr 5, 2010)

If memory serves, a power drum brake car may or may not have come with a split master cylinder. if you have a master cylinder with a front and rear reservoir, you may not have completely bench bled it, or it may have a bad piston in that section of the master. You could also have an obstruction in the rear lines, or a leak somewhere (although you'ld see fluid). 

If you're still fighting it, I'd suggest either a vacuum bleeder pulling directly from the wheel cylinder, or a pressure bleeder.


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