Caliper rebuild
Thread Starter
Navigator
Joined: Oct 2016
Posts: 9
Likes: 0
From: San Antonio tx
Caliper rebuild
I just rebuilt the calipers and replaced the master cylinder on my 77. I'm working on bleeding the system with a vacuum bleeder. I cant get the Pistons to stay in? I can push them in but they won't stay. Is this because I still have air in the line? I thought it would improve as I got more air out of the line but it hasn't. May be a dumb question but any insight would be great.
Thread Starter
Navigator
Joined: Oct 2016
Posts: 9
Likes: 0
From: San Antonio tx
The calipers are installed, the pads are tight to the rotors and won't retract unless I move them manually. When I push the brake pedal they engage but don't retract. I've never done this and they were in pretty rough shape when I took them apart, is why I'm concerned. They do have the stainless sleeves though.
Burning Brakes
Joined: Dec 2005
Posts: 1,164
Likes: 224
From: Pawleys Island, SC
They won't 'retract'. They normally are in very light contact with the rotor. The light springs behind the pistons hold them there. Are they ALL tight to the rotor? If it's just one I'd say the rubber line on that caliper is collapsed internally but if it's all of them I don't think it likely all the rubber lines are bad.
Last edited by revitup; Nov 18, 2016 at 08:19 AM.
Melting Slicks
Joined: Jul 2010
Posts: 3,176
Likes: 633
From: perth western australia
can you turn the rotor at all ? ,is it hard to turn ?
the pistons don't "back away" at all , the rotor can be turned by hand and with the road wheel on ,the front rim/tyre can be turned with one finger .
the pistons don't "back away" at all , the rotor can be turned by hand and with the road wheel on ,the front rim/tyre can be turned with one finger .
Thread Starter
Navigator
Joined: Oct 2016
Posts: 9
Likes: 0
From: San Antonio tx
I'll have to take another look at it. I replaced all the rubber hoses also. The fronts have a small gap and when the brake pedal is engaged they compress. I'll work through finishing bleeding the lines and see if anything changes. Its my first stab at this so I was questioning whether or not I had the seals on the pistons correctly.
Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
All Gm discs "dragged" on the rotors (1/60 of a horsepower). If your front pads are not contacting the rotors, something is amiss. What do you mean "the hoses compress"? The hoses will only collapse if there is a blockage in the system that is preventing the flow of brake fluid into the pistons when the pedal is released.
Last edited by jnb5101; Nov 18, 2016 at 10:12 AM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Melting Slicks
Joined: Jul 2010
Posts: 3,176
Likes: 633
From: perth western australia
What type of seal did you put in there? Was it an "O" ring type or the original style lip seal ? AND most importantly did you follow any written instructions or diagrams on how to do it..
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
