Topic: Bad Brakes - Need Ideas
in Forum: C3 Engines, Driveline and Handling
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Momence, IL - USA
Joined: 3/11/2008
Posts: 28
Vette(s): 1977 Corvette Coupe
Light Corvette Blue
One other thing, overlooked all the time when cars come into the shop here, your check valve is good on the booster? the little plastic one the vacume line hooks to? Also there is no blockage in the vacume line? Best of luck, Mike
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Thanks guys, I just got a new booster and we will try to install it this Sunday. If you want to pray for this group of men please do because we will need all the help we can get or just show up and help!!!!haha
thanks again,
michael
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When you pull the old booster off, turn it up with the master cyl side facing DOWN over a drain-pan. You'll see how much fluid is in there. It may surprise you.(or not)
The diaphragm in the booster is not brake fluid friendly...the fluid will eat at it over time, and make it weak, or even turn it hard.
If you pinch off, or otherwise plug the booster vac. line, I'll bet the engine idle will change considerably.
Tim/Dennis...Good luck with the swap, and don't let Mike be in charge of the fire extinguisher...
The diaphragm in the booster is not brake fluid friendly...the fluid will eat at it over time, and make it weak, or even turn it hard.
If you pinch off, or otherwise plug the booster vac. line, I'll bet the engine idle will change considerably.
Tim/Dennis...Good luck with the swap, and don't let Mike be in charge of the fire extinguisher...
Joel Adams
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Good luck with the brakes. Safety is always first, no matter what the cost!
Brian - NCM Lifetime Member
73 coupe L48, Flat-top pistons, Performer RPM Heads, Crane Cam and roller rockers, Holley 650 vac sec. Performer intake,
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Ellijay, GA - USA
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If the M/C and booster have been replaced and the calipers appear to be good and you bleed it and it all seems good, but then feels spongey after you drive it or gets soft after a few days.
Then you might check for proportioning valve. When they get old, they leak just a little and cause the pedal to feel soft after a few days. If they are real bad, you can see the leak, but if they are just getting old and leak just a little, you might not be able to see the leak, but after a few weeks the pedal will start to get soft.
Usually this replacement is only needed when the cars get as old as C3s. Replace it, and it will be good for another 25 years or so!
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I had the same brake problems with my '72. First I replaced one caliper that was leaking. To tell you the truth, you're better off just buying a whole new system from the beginning. I replaced all 4 calipers, the master cylinder and the hoses. I suggest upgrading to the stainless steel hoses, which will give a firmer pedal. I used regular brake fluid, and I haven't had a problem now in 8 years. Kathy
in Forum: C3 Engines, Driveline and Handling
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