[C2] brake conversion
Melting Slicks
Joined: Jul 2011
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From: Bornem
Thread Starter
Intermediate
Joined: Mar 2017
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yes, we ran new rear line to the "T" and have pumped and tried to bleed them, put a vacuum bleeder on both sides and it will hold 20lbs of vacuum until you release it. have taken the brake lines off at the rear calipers and still can't get fluid to them. pulled master cylinder forward to make sure the rod wasn't to far into master cylinder. have fluid to and thru the proportioning valve. double checked for leaks at all connections. have a good flow out of master cylinder bleeders but brake pedal doesn't feel like it builds pressure and feels like it hits the bottom limit of travel every time we try to bleed anything. we vacuumed old fluid out of rear calipers; only thing I can think of is the new "T" we installed may not have been machined correctly or drilled completely.
Safety Car
Joined: Jan 2004
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From: Macedonia Ohio
I had the same problem with my 65 when I installed Power brakes.
I also tried a vacuum bleeder with not so good results.
I bought a Motive Power Bleeder. (about $70) It uses positive pressure on the Master cylinder and pushes the fluid thru, no problem.
I also tried a vacuum bleeder with not so good results.
I bought a Motive Power Bleeder. (about $70) It uses positive pressure on the Master cylinder and pushes the fluid thru, no problem.
Thread Starter
Intermediate
Joined: Mar 2017
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we've spent about 4 hours on it after getting it installed and the only thing that is bled
is the master cylinder,( bench and about 5 times on the car) gravity should pull fluid thru the system if both ends are open and enough time, but I've got nothing coming thru the lines with all the effort we have spent.
is the master cylinder,( bench and about 5 times on the car) gravity should pull fluid thru the system if both ends are open and enough time, but I've got nothing coming thru the lines with all the effort we have spent.
Burning Brakes
Joined: Sep 2014
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From: Freehold NJ
Sometimes the piston in the proportioning valve will get jammed and will not let fluid to the rear, but a friend of mine also had a defective proportioning valve - we tried power bleeding, vacuum bleeding and conventional pumping the pedal with zero results. Changed the valve and had no problems bleeding.
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Melting Slicks
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From: merritt island fl
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Did you check for fluid at the inlet and outlets of the new tee? If good at the outlets, it could be the rubber hoses- but both sides going bad at the same time is not likely.
Team Owner
Joined: May 2005
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From: Huntsville AL
Your power brake conversion kit included a new power brake master cylinder and the associated proportioning valve, correct.
Check to see if you have fluid at the inlet of the proportioning value. If so, then check to see if you have fluid coming out of the proportioning valve.
No need to take the lines completely off, just crack them loose and push the pedal. Be sure to cover anything that can get brake fluid on it.
Just start at the master cylinder, and work your way back to each joint / fitting until you find where the fluid is NOT coming through.
Process of elimination.
Check to see if you have fluid at the inlet of the proportioning value. If so, then check to see if you have fluid coming out of the proportioning valve.
No need to take the lines completely off, just crack them loose and push the pedal. Be sure to cover anything that can get brake fluid on it.
Just start at the master cylinder, and work your way back to each joint / fitting until you find where the fluid is NOT coming through.
Process of elimination.
Thread Starter
Intermediate
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sorry I didn't get back sooner, it was over 11 hours to get a new password sent to me so I
could respond. i'll check the bottom side of proportioning valve this evening after work if I
get the chance. where would I find the post about the longer rod? nothing was mentioned
about needing that when I purchased the kit from corvette America. thanks
could respond. i'll check the bottom side of proportioning valve this evening after work if I
get the chance. where would I find the post about the longer rod? nothing was mentioned
about needing that when I purchased the kit from corvette America. thanks
Melting Slicks
Joined: Jul 2011
Posts: 2,064
Likes: 142
From: Bornem
sorry I didn't get back sooner, it was over 11 hours to get a new password sent to me so I
could respond. i'll check the bottom side of proportioning valve this evening after work if I
get the chance. where would I find the post about the longer rod? nothing was mentioned
about needing that when I purchased the kit from corvette America. thanks
could respond. i'll check the bottom side of proportioning valve this evening after work if I
get the chance. where would I find the post about the longer rod? nothing was mentioned
about needing that when I purchased the kit from corvette America. thanks
I am not a hot shot expert, but this is what I would try first cause it's simple
Last edited by alexandervdr; Jun 5, 2017 at 06:29 AM.
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From: St. Louis MO
2020 Corvette of the Year (appearance mods)
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Some master cylinders require a spacer (circled below)
Ask me how I know
Found out the hard way many years ago..
George
Ask me how I know
Found out the hard way many years ago..George
Safety Car
Joined: Jun 2000
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From: St. Louis MO
2020 Corvette of the Year (appearance mods)
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Also you may find an adjuster in the booster (see below) that will give you the correct adjustment.
George
George