Brakes won’t work.
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Joined: Sep 2019
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Brakes won’t work.
Good evening,
Im having a little trouble getting my brakes on my 76’ C3 to work. My brother in law picked it up for me and the front brakes were workin. When he got it to his house none of the brakes were working. Back brakes were disconnected. Master cylinder is new. My brother in law put new lines to the back brakes and bled the lines with his pump. The still won’t work. Any ideas? I’m going pick it up next weekend and need working brakes when I get it home. If we can’t figure it out I’m just gonna put it in the shop. Would love to fix it myself, but running out of ideas.
Im having a little trouble getting my brakes on my 76’ C3 to work. My brother in law picked it up for me and the front brakes were workin. When he got it to his house none of the brakes were working. Back brakes were disconnected. Master cylinder is new. My brother in law put new lines to the back brakes and bled the lines with his pump. The still won’t work. Any ideas? I’m going pick it up next weekend and need working brakes when I get it home. If we can’t figure it out I’m just gonna put it in the shop. Would love to fix it myself, but running out of ideas.
Is my vette stock?? HAHA
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2020 C3 of the Year Finalist - Modified
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it could be lots of air in the lines, A pressure bleeder make it a fast job.
It could be the rubber hoses going to the calipers are collapsed or clogged and they could go either way on replacing those if they are rusty
It could be water in the bake fluid is causing you problems but that is usually as they heat up and the water boils.
I would bring a gallon of brake fluid and plan on bleeding them alot.
You need to start at the passenger side rear outer bleed valve, then do the inner. ( each rear caliper has and inner and an outer, both at the top. Theres a third plug on the bottom, dont tough that)
do the drivers rear
passenger front, only one valve
drivers front.
If you take it to a shop make sure they have an old guy thats worked on corvettes before. Dont pay them the shop rate to learn on yours
It could be the rubber hoses going to the calipers are collapsed or clogged and they could go either way on replacing those if they are rusty
It could be water in the bake fluid is causing you problems but that is usually as they heat up and the water boils.
I would bring a gallon of brake fluid and plan on bleeding them alot.
You need to start at the passenger side rear outer bleed valve, then do the inner. ( each rear caliper has and inner and an outer, both at the top. Theres a third plug on the bottom, dont tough that)
do the drivers rear
passenger front, only one valve
drivers front.
If you take it to a shop make sure they have an old guy thats worked on corvettes before. Dont pay them the shop rate to learn on yours
Last edited by Rescue Rogers; Oct 6, 2019 at 09:16 AM.
Race Director
Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
Brakes are actually easy. You have a master cylinder, lines and calipers. It has to be one of the three. The steel lines rarely go bad unless they rust out. You would then see a puddle of fluid. The rubber lines you can't see if they are bad. If you don't know the condition or age replace them. They are cheap. The master cylinder? Was it bench bleed first before installing? Are you sure it is good? The calipers usually will show signs of leakage. Again puddles or fluid is present. Replace as needed. I have done dozens of brakes of C3 cars. I usually just replace it all if there is any question. Going fast is optional, stopping is mandatory! Fix the brakes right.
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Joined: Sep 2019
Posts: 60
Likes: 7
it could be lots of air in the lines, A pressure bleeder make it a fast job.
It could be the rubber hoses going to the calipers are collapsed or clogged and they could go either way on replacing those if they are rusty
It could be water in the bake fluid is causing you problems but that is usually as they heat up and the water boils.
I would bring a gallon of brake fluid and plan on bleeding them alot.
You need to start at the passenger side rear outer bleed valve, then do the inner. ( each rear caliper has and inner and an outer, both at the top. Theres a third plug on the bottom, dont tough that)
do the drivers rear
passenger front, only one valve
drivers front.
If you take it to a shop make sure they have an old guy thats worked on corvettes before. Dont pay them the shop rate to learn on yours
It could be the rubber hoses going to the calipers are collapsed or clogged and they could go either way on replacing those if they are rusty
It could be water in the bake fluid is causing you problems but that is usually as they heat up and the water boils.
I would bring a gallon of brake fluid and plan on bleeding them alot.
You need to start at the passenger side rear outer bleed valve, then do the inner. ( each rear caliper has and inner and an outer, both at the top. Theres a third plug on the bottom, dont tough that)
do the drivers rear
passenger front, only one valve
drivers front.
If you take it to a shop make sure they have an old guy thats worked on corvettes before. Dont pay them the shop rate to learn on yours
Last edited by Cdbarber; Oct 6, 2019 at 09:42 AM.
Thread Starter
Advanced
Joined: Sep 2019
Posts: 60
Likes: 7
Brakes are actually easy. You have a master cylinder, lines and calipers. It has to be one of the three. The steel lines rarely go bad unless they rust out. You would then see a puddle of fluid. The rubber lines you can't see if they are bad. If you don't know the condition or age replace them. They are cheap. The master cylinder? Was it bench bleed first before installing? Are you sure it is good? The calipers usually will show signs of leakage. Again puddles or fluid is present. Replace as needed. I have done dozens of brakes of C3 cars. I usually just replace it all if there is any question. Going fast is optional, stopping is mandatory! Fix the brakes right.
Race Director
Joined: Jul 2004
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From: Scottsdale Arizona
RR mentioned a key item above, both rear calipers have two top bleeders, inner and outer. If you don’t do both, you’ll never get all of the air out. On a particularly stubborn caliper, I’ve knocked on the side with a pice of wood to dislodge small bubbles. This is normally to get a very firm pedal though, not to get them to work at all.
Le Mans Master
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From: mount holly NC
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#2 On the rear calipers you must bleed the INNER first then the OUTER.
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
When you bench bleed, do not force the piston inside more than 1 3/8" or you will void the warranty and damage the piston seals inside. The seal will "roll-over" and catch on the casting. See my profile>album>bench bleed.
When using vacuum tool to bleed calipers, just barely crack the bleeder screw open. Just enough to get flow. More than that tends to allow air to slip past the threads. This gives the illusion in the clear tubing that a lot of bubbles are coming out, but in reality, they're not.
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Joined: Sep 2019
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Just a couple tips here:
When you bench bleed, do not force the piston inside more than 1 3/8" or you will void the warranty and damage the piston seals inside. The seal will "roll-over" and catch on the casting. See my profile>album>bench bleed.
When using vacuum tool to bleed calipers, just barely crack the bleeder screw open. Just enough to get flow. More than that tends to allow air to slip past the threads. This gives the illusion in the clear tubing that a lot of bubbles are coming out, but in reality, they're not.
When you bench bleed, do not force the piston inside more than 1 3/8" or you will void the warranty and damage the piston seals inside. The seal will "roll-over" and catch on the casting. See my profile>album>bench bleed.
When using vacuum tool to bleed calipers, just barely crack the bleeder screw open. Just enough to get flow. More than that tends to allow air to slip past the threads. This gives the illusion in the clear tubing that a lot of bubbles are coming out, but in reality, they're not.
Thread Starter
Advanced
Joined: Sep 2019
Posts: 60
Likes: 7
Just a couple tips here:
When you bench bleed, do not force the piston inside more than 1 3/8" or you will void the warranty and damage the piston seals inside. The seal will "roll-over" and catch on the casting. See my profile>album>bench bleed.
When using vacuum tool to bleed calipers, just barely crack the bleeder screw open. Just enough to get flow. More than that tends to allow air to slip past the threads. This gives the illusion in the clear tubing that a lot of bubbles are coming out, but in reality, they're not.
When you bench bleed, do not force the piston inside more than 1 3/8" or you will void the warranty and damage the piston seals inside. The seal will "roll-over" and catch on the casting. See my profile>album>bench bleed.
When using vacuum tool to bleed calipers, just barely crack the bleeder screw open. Just enough to get flow. More than that tends to allow air to slip past the threads. This gives the illusion in the clear tubing that a lot of bubbles are coming out, but in reality, they're not.