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Brakes went out and I can't find the problem

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Old 01-30-2010, 02:08 PM
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blue 67 coupe
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Default Brakes went out and I can't find the problem

Well i had noticed sometime last week the pedal was going to the floor almost and the car barely stopping in time. It go to where on my way home I had to pump the pedal twice then put the pedal down hard for it to slow down.

Got home and left it parked since then and it still has alot of brake fluid in the master cylinder. I started the car and pushed the pedal and saw no leaks anywhere. Could there be enough air in the lines for it to just about stop working? Or could the master cylinder have clogged lines? Thanks for any help.

Also its drum brakes just to claify.
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Old 01-30-2010, 02:33 PM
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rmodel65
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is the carpet inside the car wet?? might be the master cylinder leaking
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Old 01-30-2010, 02:46 PM
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blue 67 coupe
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Nope inside floorboard is completely dry. I thought just to start I was going to bleed the lines but how do I go about doing that to make sure all the air is out?
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Old 01-30-2010, 02:48 PM
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rmodel65
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well you need an assistant first


Bleeding the brakes requires a properly sized box wrench for the bleeder and the clear plastic bleed hose provided with your system. Good quality, non-silicone fluid is also a must. Baer Brakes has tested a wide variety of fluids and strongly recommends Performance Friction’s Z-Rated fluid #90016 for street and occasional track use (with Motorcraft PM1 our backup suggestion for this same duty). These two have been proven to be more effective than fluids that are often many times more expensive. For racing, Baer recommends and uses only Castrol SRF. Baer stocks and sells both the Performance Friction Z-Rated and Castrol SRF.
Always remember, good to excellent brakes or fluid do not function without adequate cooling. In fact, the more serious your brake system, the more attention that needs to be directed to proper ducting, as they will generate more heat due to increased capacity.
BLEEDING BRAKES IS NOT DONE WITH PRESSURE, IT IS PURELY A FUNCTION OF MOVING FLUID THROUGH THE SYSTEM. THE OBJECT IS TO DISPLACE AIR, NOT TO SEE HOW FAR FLUID CAN BE SHOT OUT OF THE CALIPER!
Proper Bleeding Technique
Enlist someone who will help you bleed the brakes. Make sure they also read these instructions carefully (so they understand the goal).
  1. For systems which are essentially dry front and rear, start by filling the master cylinder with proper fluid. Pour slowly so as not to aerate the fluid.
  2. Next, move to the first caliper, attach the clear plastic bleed hose to the bleeder and open it. Hold the hose upright so that you can monitor the escape of air bubbles. VERY SLOWLY stroke the brake pedal by hand or foot until fluid comes out. Now close the bleeder.
  3. ACTUAL BLEEDING SEQUENCE:
    • Have your partner very slowly, with modest pressure (approximately 25-30 lbs.ft.), stroke the pedal ONE TIME until hydraulic resistance is encountered. Ask your partner to hold at this point with the same modest and even pressure and notify you that he is “holding.”
    • Open the bleeder, letting the pedal go to the floor or until it stops, using the same modest level of pressure, then close the bleeder again. Notify your partner “the system is sealed.” He can then slowly release pedal pressure.
  4. Repeat the BLEEDING SEQUENCE (never stroke the pedal more than one time) until all signs of air are purged (no bubbles) from fluid. IMPORTANT
    • NOTE: DO NOT LET THE MASTER CYLINDER RUN DRY! Be sure to check the fluid level after every third bleeding sequence or sooner if reservoir volume is very small.
  5. Before moving to the next caliper, take a small block of wood or a plastic hammer and carefully tap the caliper to dislodge any additional air bubbles that may be trapped. Then bleed one last time.
  6. Move to the next caliper and repeat the procedures previously outlined. Continue until all calipers have been bled. Before re-installing wheels and placing the car on the ground, we recommend you carefully wipe clean all caliper surfaces, hose joints and fittings, making sure they are all dry and free from seepage. If not, inspect and tighten appropriately. Spray all rotor surfaces with Brake Kleen® or a similar product to remove all dirt and oils from your hands that may have been transferred to the rotor during assembly. Also remember to remove the nut that has been holding rotor in place before attempting to re-install the wheel.
For street use, as with any time you open the brake system, it may be advisable to repeat the bleeding procedure after driving the vehicle for a day, as driving the car may dislodge some additional air bubbles. For competition cars, we recommend repeating this procedure directly after at least the first two sessions the car is on track and at the beginning of each race weekend thereafter.
Even if your pedal is high and firm and additional bleeding is deemed unnecessary, always inspect the calipers, hoses and fittings after the first outing for signs of any fluid seepage and correct immediately.
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Old 01-30-2010, 04:07 PM
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65rangoon
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you dont really need an assistant if you have the vacuum pump.

you say they are drum, im assuming they are manual drums?

have you pulled the wheels to see if theres any fluid on the wheels/tires on the inside?

check the self adjusters. perhaps something is not working right?

spring break on the shoes?
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Old 01-30-2010, 04:37 PM
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nba1341
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Check your brakes and if you see nothing wrong then bleed

A wheel cylinder can leak slowly so you don't notice it that much until you pull the drum off. If its a cylinder you just replace it and bleed the brakes its very simple to do.
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Old 01-30-2010, 05:02 PM
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Gun Jam
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Im also guessing you have the single reservoir master cylinder (round cap) Since you are playing with bleeding brakes and almost ate it because they went out...now would be a good time to avoid doom and buy a dual MC.

-Gun
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Old 01-30-2010, 05:09 PM
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cprstreetmachines
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Sounds like it's time to buy a MC. If you have no leaks, and it doesn't stop, it's because your MC isn't building any pressure. You pump it also, you probably notice if you hold it once it builds anything, it'll bleed off.
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Old 01-30-2010, 05:21 PM
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nba1341
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Originally Posted by Gun Jam
Im also guessing you have the single reservoir master cylinder (round cap) Since you are playing with bleeding brakes and almost ate it because they went out...now would be a good time to avoid doom and buy a dual MC.

-Gun
I have the same problem how easy is it to replace the single MC with a dual MC?
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Old 01-30-2010, 05:35 PM
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Ditto, you need Dual Bowl MC. Changed my out 6 months ago when I went with discs. Also threw on a power booster. Probably not necessary to go w/ a power booster.
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