Brake Issues any ideas???
Thread Starter
Instructor
Joined: Jun 2010
Posts: 200
Likes: 0
From: queens newyork
Brake Issues any ideas???
Hey everyone I have 1989 corvette and my brakes are ushaully nice and tight, but the other night I was driving down the highway and I stepped on my brakes and my pedal went down about 80 percent and started slowing down my car and after 1 pump its back to normal, and if I try to brake like 2 mins later it will be nice a tight again but if I wait about 10 mintues the pedal will go down again and ill have to pump it again?.... any ideas? keep in mind it just started happening outa no were?
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From: So. Cal.
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Hey everyone I have 1989 corvette and my brakes are ushaully nice and tight, but the other night I was driving down the highway and I stepped on my brakes and my pedal went down about 80 percent and started slowing down my car and after 1 pump its back to normal, and if I try to brake like 2 mins later it will be nice a tight again but if I wait about 10 mintues the pedal will go down again and ill have to pump it again?.... any ideas? keep in mind it just started happening outa no were?
Thread Starter
Instructor
Joined: Jun 2010
Posts: 200
Likes: 0
From: queens newyork
yes I checked the brake fluid and its full and I also checked for some leaks and there was non that were visable and my pads are fresh. I drove it around today for a little and it was ok. I will do a complete brake fluid flush this weekend and get back to you guys.
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
Is master cylinder ok?any leaks around reservoir grommet/bore area:
first ceck for air /water in the line
1) flush the sistem,put new dot 3 into reservoir,bleed the sistem
After bleeding you have a sponge pedal?
yes
2) ceck caliper rubber lines
3)ceck mastercylinder
4)ceck valve booster
first ceck for air /water in the line
1) flush the sistem,put new dot 3 into reservoir,bleed the sistem
After bleeding you have a sponge pedal?
yes
2) ceck caliper rubber lines
3)ceck mastercylinder
4)ceck valve booster
Race Director
Joined: May 2008
Posts: 10,742
Likes: 629
From: Manheim Pennsylvania
I think you have an internal leak in the master cylinder. I have seen internal corrosion in the master cylinder so bad that the front and rear systems combined and acted as one system instead of two systems as designed.
Melting Slicks
Joined: Feb 2005
Posts: 2,057
Likes: 5
From: Bay Shore, NY
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
Maybe only temporarily - if it's pushing fluid into the rear because the seal is shot, it's going to blow the top off and you'll end up with fluid all over the battery. Was the front particularly low when you started? I'd keep a close eye on it given the symptoms - in fact go take a look now and if the back is higher and the front lower, you need a rebuild or a new Master.