Power Brakes
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Joined: Apr 2023
Posts: 9
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From: Chicago
Power Brakes
I have power brakes on the new to me '73. It sure takes a lot of pedal pressure to stop the car, sure feels like manual brakes. The car hasn't been driven in more than a week, and I just pulled off the vacuum check valve off the brake booster and there was a whoosh of air, so it seems the booster holds a good vacuum. Could a old/worn master cylinder be causing the issue?
PO put all new calipers on. The pedal doesn't feel spongy as if there is air in the lines, rather just kind of non-existent until toward the bottom where it feels like manual brakes.
Thanks in advance!
PO put all new calipers on. The pedal doesn't feel spongy as if there is air in the lines, rather just kind of non-existent until toward the bottom where it feels like manual brakes.
Thanks in advance!
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
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you could have bad pads that have seen too much heat. It happens with organic pads a lot and they will feel like stepping on a brick. You already checked the booster so thats not it. You could have collapsed rubber flex lines at the calipers. You wouldnt be able to see a visual difference unless they were so bad the had bulges. You can bleed each corner and see if you get a steady stream, if so they are still probably good. If the pads are bad you can get some good ceramic pads, they will stop on a dime but depending on the friction coefficient you go with they could be dusty. They have to be bedded in. Read the directions that come with them
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Lot of "Could be's". Pads causing the effect you describe, doesn't make sense to me.
wrong master, incorrectly adjusted pushrod on master would be the things I would look at.
Another thing that comes to mind is the safety valve that many think is a proportioning valve. If it's kicked to one side from the brake bleeding procedure when the new calipers were installed you would only be getting brakes on either the front or rear but not both.
usually a few sharp stabs on the brake pedal will recenter it.
wrong master, incorrectly adjusted pushrod on master would be the things I would look at.
Another thing that comes to mind is the safety valve that many think is a proportioning valve. If it's kicked to one side from the brake bleeding procedure when the new calipers were installed you would only be getting brakes on either the front or rear but not both.
usually a few sharp stabs on the brake pedal will recenter it.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,153
Likes: 9,283
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
when I went to a track day with newer organic pads they performed fine during the racing and the drive home. Then next day I couldnt stop to save my life. Put in new ceramic pads and it was as good as new
