Mushy brake after rear disc kit install, help! - Team Camaro Tech
Brakes, Suspension & Steering Conversion questions, Steering & Handling

 
LinkBack Thread Tools Display Modes
post #1 of 7 (permalink) Old Jun 19th, 10, 02:25 AM Thread Starter
Gold Lifetime Member
Dave
 
Join Date: Jun 2006
Location: Vacaville CA
Posts: 1,359
Mushy brake after rear disc kit install, help!

I can't get the rear brakes to hold a good pedal. I can pump up the brakes, but they go soft right away. Usually 2 pumps and the pedal feels good again.

Also when I get a good pedal and I start the engine the pedal will go to the floor.

How can you tell which pin to use between and booster and the m/c? I have new booster and a new m/c so I can't go by my old parts. The cup on the m/c has a hole that goes in about an inch. It's a "309" copy. The booster is a Delco/Moraine stamp repo.


Suggestions?

Dave

Known to run with scissors....
__________
1969 Camaro Z/28 "clone", GMPP ZZ383, Autogear M22W, Moser 12bolt w/TruTrac 3:73.
Fred Mertz is offline  
Sponsored Links
Advertisement
 
post #2 of 7 (permalink) Old Jun 19th, 10, 04:34 AM
Senior Tech
Greg
 
Join Date: Sep 2007
Location: S. Florida
Posts: 1,222
Re: Mushy brake after rear disc kit install, help!

Sure sounds like you have air in your lines. How did you bleed the brakes?

1969 RS/SS Vert

1031 Engineering llc
chops is offline  
post #3 of 7 (permalink) Old Jun 19th, 10, 06:49 AM
Senior Tech
Dan
 
Join Date: May 2003
Location: Fort Lauderdale Fla.
Posts: 237
Re: Mushy brake after rear disc kit install, help!

Fred, Were your rear calipers adjusted out mechanically before the bleeding process? I had to adjust the e-brake lever on mine (79 trans-am) type rear calipers that maybe it

68 camaro RS 327/275 THM350 4 wheel disc brake 8.5 10 bolt 3.42 daily driver
icpop is offline  
 
post #4 of 7 (permalink) Old Jun 19th, 10, 08:14 AM Thread Starter
Gold Lifetime Member
Dave
 
Join Date: Jun 2006
Location: Vacaville CA
Posts: 1,359
Re: Mushy brake after rear disc kit install, help!

We did bleed the brakes before getting the e-brake set right. But since getting the e-brake adjusted we have bleed the brakes repeatedly.

Dave

Known to run with scissors....
__________
1969 Camaro Z/28 "clone", GMPP ZZ383, Autogear M22W, Moser 12bolt w/TruTrac 3:73.
Fred Mertz is offline  
post #5 of 7 (permalink) Old Jun 19th, 10, 08:41 AM
Senior Tech
Bob
 
Join Date: Jun 2000
Location: Half Moon Bay,Ca.
Posts: 522
Re: Mushy brake after rear disc kit install, help!

Dave..Mine is almost ready to be bled.I still having problems adjusting the e-brake.
I just checked my master cylinder from the kit.Mine has a 2" bore and
I set it up with the longer of the two rods.

" Some like it Hot, I like it Red "... Sammy Hagar
'69 Coupe...Red of course!


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Red Rocker is offline  
post #6 of 7 (permalink) Old Jun 19th, 10, 09:36 AM
Senior Tech
Tony
 
Join Date: Dec 2000
Location: Willow Park, Texas
Posts: 1,030
Re: Mushy brake after rear disc kit install, help!

Quote:
Originally Posted by Fred Mertz View Post
I can't get the rear brakes to hold a good pedal. I can pump up the brakes, but they go soft right away. Usually 2 pumps and the pedal feels good again.

Also when I get a good pedal and I start the engine the pedal will go to the floor.

How can you tell which pin to use between and booster and the m/c? I have new booster and a new m/c so I can't go by my old parts. The cup on the m/c has a hole that goes in about an inch. It's a "309" copy. The booster is a Delco/Moraine stamp repo.


Suggestions?
Dave,

Sounds like your master is leaking either into the booster or bypassing internally (between the pistons). I had this years ago when I first got the car running and I had a "New" Master on the car. It was bypassing internally, I could pump the pedal and it would be very hard then slowly get spongy and push to the floor.

Tony:
67 RS Clone, 388 SBC/Keisler TKO 600/12 bolt, 3.90 gear w/posi and a 250 shot of N2O for fun. See my progress at: password is camaro


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
idoxlr8 is offline  
post #7 of 7 (permalink) Old Jun 19th, 10, 03:54 PM Thread Starter
Gold Lifetime Member
Dave
 
Join Date: Jun 2006
Location: Vacaville CA
Posts: 1,359
Re: Mushy brake after rear disc kit install, help!

Tada! Finally have brakes. We found a leak in the line that runs fromthe rear flex hose between the body and the top of the diff. Once that was fixed we started to get better pedal feel.
We would get good pedal but lose the pedal when the booster line to intake manifold was hooked up. We tested the booster to see if it would hold vacuum. It would not. Also tested another new booster that I have. It would also not hold vacuum. we ended up put the original booster back on the car.

At this time I do have brakes.

Dave

Known to run with scissors....
__________
1969 Camaro Z/28 "clone", GMPP ZZ383, Autogear M22W, Moser 12bolt w/TruTrac 3:73.
Fred Mertz is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome