Brakes won’t work
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Joined: Oct 2019
Posts: 97
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From: Miami
Brakes won’t work
Ok, so I’ve finally been able to install a new brake caliper in my car as the old right passenger caliper was leaking. The master cylinder was also rusty so it was replaced. After bleeding the brakes the car still wouldn’t brake properly. I have to fully depress the pedal in order to stop and if I brake hard the wheels lock up very fast. Also the pedal kind of pushes back against my foot. There isn’t much resistance on the brake pedal when the car is on. It feels normal when the car is off. I don’t know why the brakes won’t work, I’m going to have a friend of mine who has more experience bleed the brakes again and I hope that might fix it. Im also worried it might be the proportioning valve. I don’t know a lot about brakes so I was hoping someone with more experience could help me out. My car is a 71 with power discs on all wheels. Also the new caliper I bought is rubbing on the wheel. I have American racing wheels.
Last edited by Gabriel Vianna; Feb 8, 2020 at 09:54 PM.
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Did the old caliper rub the wheel?
if not either the caliper is not installed correctly, the wheel is not installed correctly or the wheels are not intended for your car.
When you replaced the caliper, did the master cylinder completely empty?
What sequence did you bleed the brakes and what method?
if not either the caliper is not installed correctly, the wheel is not installed correctly or the wheels are not intended for your car.
When you replaced the caliper, did the master cylinder completely empty?
What sequence did you bleed the brakes and what method?
Last edited by MelWff; Feb 8, 2020 at 10:14 PM.
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Joined: Oct 2019
Posts: 97
Likes: 6
From: Miami
Did the old caliper rub the wheel?
if not either the caliper is not installed correctly, the wheel is not installed correctly or the wheels are not intended for your car.
When you replaced the caliper, did the master cylinder completely empty?
What sequence did you bleed the brakes and what method?
if not either the caliper is not installed correctly, the wheel is not installed correctly or the wheels are not intended for your car.
When you replaced the caliper, did the master cylinder completely empty?
What sequence did you bleed the brakes and what method?
Thread Starter
Advanced
Joined: Oct 2019
Posts: 97
Likes: 6
From: Miami
Thread Starter
Advanced
Joined: Oct 2019
Posts: 97
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From: Miami
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Yes I am well aware, I purchased an aluminum MC from pirate jack racing which is a GM universal unit. I called them and asked if I needed to order a PWR version but they said it worked with both. There is an adapter which I will include pictures of, that came in the box. I tried installing it but it didn’t work. Also my brakes don’t lock up quick they lock up when the pedal is on the floor with more pressure being applied to it.
I know you don't want to hear this, but go back to Delco Remy. (rebuilt) on the master & calipers. They are specific fit, where as some Delcos Chevy parts fit Chevelles, Novas, Impallas, etc. Master cylinders are very-very specific what they fit in the C3 world. Its all about the booster rod gap and the MC piston inside.
And caliper fitment is very specific too. Front or back. Left or right. Its all about the bleeder screw location.
Proportioning Valves seldom fail. There not mush inside them to go wrong so I don't that is an issue.
Take a look at my profile, photo album, bleeding brakes for info.
Last edited by HeadsU.P.; Feb 9, 2020 at 11:48 AM.
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Thread Starter
Advanced
Joined: Oct 2019
Posts: 97
Likes: 6
From: Miami
Ahhh. There's the problem. After market stuff that is suppose to fit. Asterisk says: but not C3 Vettes.
I know you don't want to hear this, but go back to Delco Remy. (rebuilt) on the master & calipers. They are specific fit, where as some Delcos Chevy parts fit Chevelles, Novas, Impallas, etc. Master cylinders are very-very specific what they fit in the C3 world. Its all about the booster rod gap and the MC piston inside.
And caliper fitment is very specific too. Front or back. Left or right. Its all about the bleeder screw location.
Proportioning Valves seldom fail. There not mush inside them to go wrong so I don't that is an issue.
Take a look at my profile, photo album, bleeding brakes for info.
I know you don't want to hear this, but go back to Delco Remy. (rebuilt) on the master & calipers. They are specific fit, where as some Delcos Chevy parts fit Chevelles, Novas, Impallas, etc. Master cylinders are very-very specific what they fit in the C3 world. Its all about the booster rod gap and the MC piston inside.
And caliper fitment is very specific too. Front or back. Left or right. Its all about the bleeder screw location.
Proportioning Valves seldom fail. There not mush inside them to go wrong so I don't that is an issue.
Take a look at my profile, photo album, bleeding brakes for info.
Thread Starter
Advanced
Joined: Oct 2019
Posts: 97
Likes: 6
From: Miami
I’ll try bleeding the brakes one more time and then I’ll give you an update on the situation. One more thing, I forgot to put the cover on the MC and when I pressed the brake pedal in a good amount of fluid shot up and out of the master cylinder. Is that normal or should the fluid be going into the brake calipers and some sort of pressure relief systems is not allowing that to happen?
Pro
Joined: Jun 2016
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From: Auckland
Thread Starter
Advanced
Joined: Oct 2019
Posts: 97
Likes: 6
From: Miami
Le Mans Master
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From: Cool Northern Michigan
The pedal travel distance is shorter than most cars so it takes a longer period to flush the air out.
I have had decent luck with the vacuum method. Motive Pressure is better and some prefer gravity bleed. Why? You never touch the pedal.
And for what its worth, when using a vacuum pump tool, don't open the bleeders too far. Air will leak past the threads. Open just enough to get flow.
Last edited by HeadsU.P.; Feb 10, 2020 at 06:35 PM.
Pro
Joined: Jun 2016
Posts: 567
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From: Auckland
You have it backwards. Pedal method does not work well. It trips the Proportioning Valve activating the brake warning light.
The pedal travel distance is shorter than most cars so it takes a longer period to flush the air out.
I have had decent luck with the vacuum method. Motive Pressure is better and some prefer gravity bleed. Why? You never touch the pedal.
The pedal travel distance is shorter than most cars so it takes a longer period to flush the air out.
I have had decent luck with the vacuum method. Motive Pressure is better and some prefer gravity bleed. Why? You never touch the pedal.
I also prefer the motive bleeder, forgot to mention it in my last post.
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,025
From: New Braunfels Texas
Gravity bleed the brakes........do one at a time starting with the right rear........pop a cold beverage and wait for it.......I have a Roku in the garage and recently sat and watched a movie while gravity bleeding a 71' Demon that I put a Wilwood disc brake kit on.......all new lines, pop valve, master, etc........took three hours all the way around. Once all of the bleeders were closed.....perfect pedal and stopping. Hell, my buddy in Michigan replaced his front calipers on a 2010 Silverado....ask me how to bleed it and told him gravity.......worked for him on a modern ABS equipped truck!
Try it....it just works.....and no special tools necessary! Hydraulic fluid will find its path and take all of the air with it........in fact, most hydraulic equipment is bled this way.
Jebby
Try it....it just works.....and no special tools necessary! Hydraulic fluid will find its path and take all of the air with it........in fact, most hydraulic equipment is bled this way.
Jebby