Need brake help
Thread Starter
Intermediate
Joined: May 2004
Posts: 28
Likes: 0
From: Soddy Daisy TN
Need brake help
I have a 71 350. I recently replaced the master cylinder to improve my brakes that didn't work well. The booster seems to work well, I bled all four wheels, and there are no leaks at the calipers or elsewhere. But the same problem continues the pedal goes nearly to the floor and has very little braking power. They barely hold the car on a slight incline and have very little stopping power. I'm not sure what else to do any suggestions? Thank you
Melting Slicks
Joined: Aug 2003
Posts: 2,135
Likes: 2
From: Dayton Oh
Brakes can be frustrating. When I replace my rear calipers a few weeks ago, I had the same problem as you. Even though it seemed that I bleed the lines good, I couldn't get much petal. After giving up, I let it sit all night and the next morning, I bleed the brakes again: RR, LR, RF, LF. I got good petal instantly. The only thing I figure happened was that I must have had an air bubbles somewhere and letting sit all night allowed them to finally get collected enough to bleed out. Good luck and give it a try after sitting for a while.
Melting Slicks
Joined: Oct 2001
Posts: 3,025
Likes: 12
From: Pleasant Grove AL
First question is whether you bench bled the master cylinder prior to installation. If not, they are very hard to get bled once in place. A couple of other things that could be causing problems, the rear calipers have two bleeders-did you bleed both? Also, sometimes air can get trapped in the tops of the calipers. It may help to lightly rap with a plastic hammer while bleeding.
The best suggestion is to buy, borrow, or steal a pressure bleeder. You can buy one that works with your car for about $50. An excellent investment if you work on brakes much. Also makes it easy to do a perodic brake fluid change, which is highly recommended if your car isn't a daily driver.
The best suggestion is to buy, borrow, or steal a pressure bleeder. You can buy one that works with your car for about $50. An excellent investment if you work on brakes much. Also makes it easy to do a perodic brake fluid change, which is highly recommended if your car isn't a daily driver.
Melting Slicks
Joined: May 2002
Posts: 2,508
Likes: 0
From: Wisconsin
I have the exact same problem. How well do the rear brakes bleed? Does a good amount of fluid come out? If not, the little balance bar thing might be closing off that side. You have to let it return to center. Another thing is that I guess you're no longer supposed to pump the brake pedal when bleeding. That was only for cars in the 50's. Just constant slow pressure down. Let it up slow, and then back down when bleeding. This keeps that balance bar thing centered. I've got another master cylinder coming this morning and I'll hopefully be trying this procedure out. It's what my dad's mechanic friends were saying to do, and two of them had or currently have C3s.
