C3 Gravity Bleed
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Instructor
Joined: Apr 2005
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From: webster ny
C3 Gravity Bleed
I decided to try gravity bleeding as I have alot of time.
I cracked open all the bleeders, and attached hose to them, to drain the fluid.
After about 5 hours very little has bled out of the bleeders. Perhaps 1/8 of a inch less in the MC if that much.
Update:
I closed all bleeders less the rear passenger and decided to do one at a time.
So far still not bleeding much. Perhaps it takes a while?
Thanks,
Hef
I cracked open all the bleeders, and attached hose to them, to drain the fluid.
After about 5 hours very little has bled out of the bleeders. Perhaps 1/8 of a inch less in the MC if that much.
Update:
I closed all bleeders less the rear passenger and decided to do one at a time.
So far still not bleeding much. Perhaps it takes a while?
Thanks,
Hef
Last edited by Hef; Jun 18, 2011 at 06:54 PM.
Instructor
Joined: Apr 2002
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From: parsippany nj
Make sure that the master cylinder lid is not clamped on--it may create a vacuum. I just bled my car today and it worked well. I made sure the tubing going from the bleeder was horizontal at some point so that air could not get in the line
Burning Brakes
Joined: Jan 2006
Posts: 1,223
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From: Fort Wayne IN
I don't remember it taking too long to drain the MC completely, If you left it overnight I'm sure the lines would be completely drained.
Burning Brakes
Joined: Dec 2007
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Thanks for that advice. <My pedal is very soft and the brakes barely work. When I get the interior done I'll put it up on stands and try the gravity bleed. Car looks like it has the Original M/C ('74).
Ensure you leave the MC lid off, I did it with the car level and it worked fine. If you are not getting very much flow with the bleeder wide open and the MC lid off, perhaps you have a passage or line gummed up somewhere.
I don't remember it taking too long to drain the MC completely, If you left it overnight I'm sure the lines would be completely drained.
I don't remember it taking too long to drain the MC completely, If you left it overnight I'm sure the lines would be completely drained.
Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
I completed replaced all the fluid in my brake system in about 3 hours one afternoon using the gravity method. I spent the majority of the time tinkering around in the shop and topping off the fluid from time to time. I did one wheel at a time. It was the first time I had used the gravity method and I was surprised at how smoothly it went. I realize others haven't had it as easy.
DC
DC
Burning Brakes
Joined: Dec 2007
Posts: 889
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Noticable improvement and pedal feel???
I completed replaced all the fluid in my brake system in about 3 hours one afternoon using the gravity method. I spent the majority of the time tinkering around in the shop and topping off the fluid from time to time. I did one wheel at a time. It was the first time I had used the gravity method and I was surprised at how smoothly it went. I realize others haven't had it as easy.
DC
DC
Navigator
Joined: Jun 2011
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Brakes Problems????
Hello, I just bought a 1973 corvette convertible and having brake problems feel sluggish! I know I can bleed the brakes and expect a little better braking, but I would like to do a little road racing with my corvette in the future and I have "Mannuel Brakes" ?...
1. Can I lock my brakes at any speed with this system when it is working properly or should I upgrade the master cylinder? Note I just bought some "Bear Claw Brakes" so that's takes care of that?
2. Or do I need to go with a power master cylinder? "don't really want to go through that process" I went through this with my 1965 mustang fastback. I sold to buy the vette, so I have never had a corvette and know nothing about them any help would be great.
Thanks for any info, it seems that you guys know what your talking about.
1. Can I lock my brakes at any speed with this system when it is working properly or should I upgrade the master cylinder? Note I just bought some "Bear Claw Brakes" so that's takes care of that?
2. Or do I need to go with a power master cylinder? "don't really want to go through that process" I went through this with my 1965 mustang fastback. I sold to buy the vette, so I have never had a corvette and know nothing about them any help would be great.
Thanks for any info, it seems that you guys know what your talking about.
Last edited by Topgun1; Jun 18, 2011 at 09:29 PM.
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Thread Starter
Instructor
Joined: Apr 2005
Posts: 101
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From: webster ny
Ensure you leave the MC lid off, I did it with the car level and it worked fine. If you are not getting very much flow with the bleeder wide open and the MC lid off, perhaps you have a passage or line gummed up somewhere.
I don't remember it taking too long to drain the MC completely, If you left it overnight I'm sure the lines would be completely drained.
I don't remember it taking too long to drain the MC completely, If you left it overnight I'm sure the lines would be completely drained.
Very odd!
I did notice the fluid in the MC (rear half) looked cloudy.
Hef
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From: Corsicana, Tx
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I just did mine today when I installed some new calipers. It took all of about 2-3 minutes for fluid to start coming out of each bleeder. I had all 4 open and by the time I had worked my way around the car and waited about a minute the first one was flowing...then progrsssively each one started in order.
I have had them where it took a slight pedal push to get them flowing.
JIM
I have had them where it took a slight pedal push to get them flowing.
JIM
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Joined: Jun 2011
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From: Detroit
Hi Hef
Just wanted to comment. i just got a 79 that has been sitting for almost 20 years so everything was replaced. I would suggest looking at the rubber lines from the frame to the swing arm and the steel lines from the swing arm to the rear caliper. the rubber can breakdown. I had some gunk ( technical term) in there and had a friend push and hold the break peddle to get the fluid moving. fill the MC and set the cap on with 1 clip and have a friend push and hold the break peddle and start at the RR caliper and just crack the bleeder screw closest to you, the one on the outside and work back to the frame. my calipers had 2 bleed screws and they both needed to be blead. Just take your time and check your fluid level’s and make sure your friend doesn’t go crazy with the pumping action.
Just wanted to comment. i just got a 79 that has been sitting for almost 20 years so everything was replaced. I would suggest looking at the rubber lines from the frame to the swing arm and the steel lines from the swing arm to the rear caliper. the rubber can breakdown. I had some gunk ( technical term) in there and had a friend push and hold the break peddle to get the fluid moving. fill the MC and set the cap on with 1 clip and have a friend push and hold the break peddle and start at the RR caliper and just crack the bleeder screw closest to you, the one on the outside and work back to the frame. my calipers had 2 bleed screws and they both needed to be blead. Just take your time and check your fluid level’s and make sure your friend doesn’t go crazy with the pumping action.
Burning Brakes
Joined: Aug 2008
Posts: 878
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From: Deep South Denmark
If that one is colapsed maybe the rest of them are on their way.
I just gravity bled mine, two at a time, and it took no longer than 20 minutes to almost drain the MC.
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
If you're fortunate enough to actually have the bleeder's break loose, probably a good idea to replace them, as could be clogged and not that expensive. I use a Mity-Vac tool for this, and not that expensive either.
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From: webster ny
Did you replace the hoses at the calipers? They sometimes colapse. Try dismantling the hose from the hard brake line at the passenger rear and se if brake fluid comes out of the hard line.
If that one is colapsed maybe the rest of them are on their way.
I just gravity bled mine, two at a time, and it took no longer than 20 minutes to almost drain the MC.
If that one is colapsed maybe the rest of them are on their way.
I just gravity bled mine, two at a time, and it took no longer than 20 minutes to almost drain the MC.
Yes I need to replace them. I was hoping to at least get things moving in the system to see if any of the caliper lip seals are leaking also.
Do you guys recommend the Ecklers stock parts, or can a chain auto store brake lines/hoses do the job?
The steel lines are OEM. Should I replace them all, or just the one that connects to the caliper?
The car has always been stored inside.
Below is a kit from Eckers.
http://www.ecklers.com/productmedia/.../4620/image/0/
Thanks,
Hef
Last edited by Hef; Jun 19, 2011 at 07:32 AM.
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From: Detroit
i am lucky enough that this place http://www.tracyvette.com/ is near my house. i like to get stuff local.
when i got 4 calipers and my MC the guy put the steel lines from the caliper to the rubber hose and i belive my rubber lines are OEM also. but i didnt replace any lines that were not dammaged
when i got 4 calipers and my MC the guy put the steel lines from the caliper to the rubber hose and i belive my rubber lines are OEM also. but i didnt replace any lines that were not dammaged
Burning Brakes
Joined: Aug 2008
Posts: 878
Likes: 55
From: Deep South Denmark
Dont laugh - I think my hoses are OEM.
Yes I need to replace them. I was hoping to at least get things moving in the system to see if any of the caliper lip seals are leaking also.
Do you guys recommend the Ecklers stock parts, or can a chain auto store brake lines/hoses do the job?
The steel lines are OEM. Should I replace them all, or just the one that connects to the caliper?
The car has always been stored inside.
Below is a kit from Eckers.
http://www.ecklers.com/productmedia/.../4620/image/0/
Thanks,
Hef
Yes I need to replace them. I was hoping to at least get things moving in the system to see if any of the caliper lip seals are leaking also.
Do you guys recommend the Ecklers stock parts, or can a chain auto store brake lines/hoses do the job?
The steel lines are OEM. Should I replace them all, or just the one that connects to the caliper?
The car has always been stored inside.
Below is a kit from Eckers.
http://www.ecklers.com/productmedia/.../4620/image/0/
Thanks,
Hef
Looks fine from the outside:
Same hose, not so fine inside:
/Karsten
Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
Thread Starter
Instructor
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From: webster ny
Update to Gravity Bleeding
Update:
Well I gravity bled the two rear, and the front passenger.
The drivers side front is another story.
With the bleeder removed no brake fluid came out.
Using a vacuum pump on the bleeder, I was able to suction out some fluid, but I could not get the flow started on its own with gravity.
I even tried conventional bleeding pumping the pedal, then opening the valve, but no fluid came out still!
Apparently I have a clog in perhaps the rubber hose.
Hef
Well I gravity bled the two rear, and the front passenger.
The drivers side front is another story.
With the bleeder removed no brake fluid came out.
Using a vacuum pump on the bleeder, I was able to suction out some fluid, but I could not get the flow started on its own with gravity.
I even tried conventional bleeding pumping the pedal, then opening the valve, but no fluid came out still!
Apparently I have a clog in perhaps the rubber hose.
Hef