brake
Thread Starter
Race Director
Joined: Aug 2002
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From: Boone NC home of 3peat National Champs ASU Mountaineers
St. Jude Contributor
brake
Folks I have a 79 and the right side calipers were holding the rotor. I replaced the calipers and still have some grabbing. The brake pedal is okay at first but after the engine is started it goes to the floor. Is it the master cylinder? If I bleed it, the rotor turns. Any body got any ideas?
Le Mans Master
Joined: Jan 2000
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From: New Hill NC
Adjust the push rod so that when the brake is not applied the pickup hole vent in the bottom of the master cylinder is uncovered. This allows the fluid to be picked up and lets the fluid pressure balance itself. Then bleed the brakes to get the air out. Also check the flow through in the rubber lines.
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From: Boone NC home of 3peat National Champs ASU Mountaineers
St. Jude Contributor
Where is the push rod? in the front of the mc? My friend said that the line may be collapsing on the inside of the line.
Le Mans Master
Joined: Jan 2000
Posts: 8,918
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From: New Hill NC
You should check the rubber hoses first. Jack up the car. Apply the brakes. Then try to turn the wheels. If one or more is hard to turn, loosen the bleeder on that one and see if it releases. If so, it has bad hoses. If you find all of that OK, then go to the MC. If you look down in the bottom of the MC, you will see some holes. If the piston in the MC does not come back far enough to clear the holes, you will have to adjust the rod. Some are adjustable, some are not. You have to pull the MC off and forward to get to the rod.
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From: Boone NC home of 3peat National Champs ASU Mountaineers
St. Jude Contributor
You should check the rubber hoses first. Jack up the car. Apply the brakes. Then try to turn the wheels. If one or more is hard to turn, loosen the bleeder on that one and see if it releases. If so, it has bad hoses. If you find all of that OK, then go to the MC. If you look down in the bottom of the MC, you will see some holes. If the piston in the MC does not come back far enough to clear the holes, you will have to adjust the rod. Some are adjustable, some are not. You have to pull the MC off and forward to get to the rod.
I think i'll change the right side hose and see if it changes.
Le Mans Master
Joined: Jan 2000
Posts: 8,918
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From: New Hill NC
Right side is not turning after the brake is applied. If I burp the bleeder it releases. I haven't checked the rears. When I have the engine on the brakes go all the way to the floor or the vacuum isn't working on the power booster.
I think i'll change the right side hose and see if it changes.
I think i'll change the right side hose and see if it changes.
Thread Starter
Race Director
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From: Boone NC home of 3peat National Champs ASU Mountaineers
St. Jude Contributor
Thread Starter
Race Director
Joined: Aug 2002
Posts: 17,198
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From: Boone NC home of 3peat National Champs ASU Mountaineers
St. Jude Contributor
on all 4 or just the one replaced. Chiltons said just to bleed out the one changed. Plenty of petal now, but turn on the car and the petal goes to the floor. Do I still have air in the caliper?
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Burning Brakes
Joined: Jun 2005
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From: THE OLDER I GET THE BETTER I WAS! NORTHERN ONTARIO
Heel & Toe
Joined: Jan 2007
Posts: 22
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I do think so...there is a procedure for bleeding i jinda forget but it should be in a manual...I think it starts inboard bleeder left rear then out board bleeder left rear left front then right rear & then the right front...something like that made a big difference for me
I remember that happening to my Dad's 81. What we did was leave the bleeders open over night then plug them and it worked. just make sure if you do this leave something under the bleeder to catch the fluid that will leak out. We didn't and kinda made a mess...
Drifting
Joined: Oct 2004
Posts: 1,259
Likes: 7
From: Ontario
You may be dealing with two problems. But for sure your hoses are bad...they retain pressure and degrade from the inside. As per the above posts.... start fresh with all new hoses and re-bleed then see what you have. You could be correct about the vacume assist, but do the hoses first.
Drifting
Joined: Nov 2003
Posts: 1,634
Likes: 4
From: Northern NJ
St. Jude Donor '04 & '05
As far as you locking issue, also make sure you have 1/16 - 1/8" end play between the pedal and the MC push rod. And lastly check the brake switch itself. I recently had a bad switch which was keeping the pedal from fully returning when released. FWIW.
Good Luck!
