78 Brakes Problem
Thread Starter
Intermediate
Joined: May 2008
Posts: 32
Likes: 0
78 Brakes Problem
I took my 78 to work today. I must have pulled the parking brake to far and I couldn't release it. With the parking brake still on, I then moved the car about a foot forward and backward. I was then able to finally release it. As soon as I did this I felt the brake pedal go to the floor. Now my brake light stays on and the pedal just about touches the floor. The master cylinder was low so I added fluid (too much of course!), pumped the brakes and it still goes to the floor.
I don't see any fluid leaking anywhere at all. I took the car to a mechanic and they pulled all four wheels off and couldn't find any fluid leaks. They're not sure what it can be. I have to take it back to them next week so they can spend more time on it.
Any ideas on what could be wrong?
Thanks.
I don't see any fluid leaking anywhere at all. I took the car to a mechanic and they pulled all four wheels off and couldn't find any fluid leaks. They're not sure what it can be. I have to take it back to them next week so they can spend more time on it.
Any ideas on what could be wrong?
Thanks.
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
On the '78 I had I experienced a problem of low pedal and no leakage of fluid. The brake light would come until the lines were bled...several times it happened.
My problem was a caliper seal was bad...it didn't leak...it sucked air in. Rebuilding the caliper cured the problem.
You may have a different issue since yours occurred after a parking brake problem. I'm just relating what I experienced.
My problem was a caliper seal was bad...it didn't leak...it sucked air in. Rebuilding the caliper cured the problem.
You may have a different issue since yours occurred after a parking brake problem. I'm just relating what I experienced.
Le Mans Master
Joined: Sep 2002
Posts: 5,236
Likes: 898
From: Myrtle Beach SC
How low was the fluid? If low enough, air could have entered the master cylinder which means removing the M/C and bench bleeding.
Sounds like you're not getting any pressure on the pedal which means air in the system. May have to bleed entire system but I think Roughrider is pointing out a greater problem.
When were you brakes last rebuilt? It may be time...Mechanics will spend much (and $) to troubleshoot the system. It may be time to upgrade your brake system to stainless steel calipers with the O rings.
Sounds like you're not getting any pressure on the pedal which means air in the system. May have to bleed entire system but I think Roughrider is pointing out a greater problem.
When were you brakes last rebuilt? It may be time...Mechanics will spend much (and $) to troubleshoot the system. It may be time to upgrade your brake system to stainless steel calipers with the O rings.
C6 the C5 of tomorrow
Joined: Nov 2000
Posts: 6,665
Likes: 2
From: Twin Cities Minnesota
The parking brake is a completely seperate system from the normal brakes,the only part in common is the rotor.
I'm pretty sure, it's purely coincidence that the brakes failed when they did.
I'm also pretty sure you have air in the lines and /or bad flex lines.
if there is air in the lines you should be able to pump up the pedal. It will then be ok as long as you keep pressure on the pedal.
If the master is bad you can pump it up ( sometimes ) then it will slowly sink to the floor if you keep pressure on the pedal.
It seems the only real way to fix these brakes sometimes it to rebuild everything. All the calipers, flex lines and master clyinder.
Keith
Corvette Engineering
I'm pretty sure, it's purely coincidence that the brakes failed when they did.
I'm also pretty sure you have air in the lines and /or bad flex lines.
if there is air in the lines you should be able to pump up the pedal. It will then be ok as long as you keep pressure on the pedal.
If the master is bad you can pump it up ( sometimes ) then it will slowly sink to the floor if you keep pressure on the pedal.
It seems the only real way to fix these brakes sometimes it to rebuild everything. All the calipers, flex lines and master clyinder.
Keith
Corvette Engineering
Thread Starter
Intermediate
Joined: May 2008
Posts: 32
Likes: 0
The master took 1/2 bottle of fluid to fill, but that was actually too much because some came out when I put the cap back on the cylinder.
I can't pump the pedal up. It just goes to the floor and doesn't build any pressure.
I can't pump the pedal up. It just goes to the floor and doesn't build any pressure.
