Brake Questions - Help - Mopar Forums

Brake Questions - Help

Reply

 
 
 
Old 05-13-2018, 06:16 PM
  #1  
New Member
Thread Starter
 
Join Date: May 2018
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Brake Questions - Help

New to the Forum, Hello All. I am working on a 1969 Barracuda that I recently purchased. I DO NOT have the build sheet and need some ideas on the direction I need to go on a brake repair. The vehicle is a 340 small block with front discs and rear drums. Here are the questions. Note : Please forgive me, I have done brake jobs but I am lacking information on the vehicle specifications here.

1) How would I know if the front disk brakes were factory installed or after-market? One of the pictures below shows the caliper and you can see "A71312" on the passenger side one.

2) Is the picture below a proportioning valve or a distribution block? I am concerned someone just threw on front disc brakes and did not install a proportioning valve nor install the correct master cylinder.

3) The master cylinder is manual and there is a "20872" stamped in the rubber seal gasket and made in "U.S.A." BUT both chambers are the same size/volume like it is for a 4 wheel drum car. Again, I am concerned someone bush-leagued the brakes and did not install a proportioning valve the correct MC.

4) The vehicle does not seem to lock up the rear wheels when braking and without a proportioning valve that would happen, right?

- Will
Attached Thumbnails Brake Questions - Help-20180513_140214_scaled.gif   Brake Questions - Help-20180513_140847_scaled.gif  
dennisonwj is offline  
Reply With Quote
Old 05-13-2018, 08:20 PM
  #2  
Mopar Lover
 
RacerHog's Avatar
 
Join Date: Jun 2013
Location: Monrovia SO-CAL (USA)
Posts: 7,044
Thanked 499 Times in 495 Posts
As far as I know... No Disc factory installed in 69...
Not sure the bleeder screw should be pointing down... Leads me to thinks is some type of aftermartket..
Yes that is a proportioning valve...
RacerHog is offline  
Reply With Quote
Old 05-13-2018, 08:30 PM
  #3  
New Member
Thread Starter
 
Join Date: May 2018
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by RacerHog View Post
As far as I know... No Disc factory installed in 69...
Not sure the bleeder screw should be pointing down... Leads me to thinks is some type of aftermartket..
Yes that is a proportioning valve...
On another forum, people told me it was NOT a proportioning valve, but a distribution block instead.
That is not the bleeder screw but where the hard line attaches from the soft rubber line, the bleeder is on the other side of the stem coming out the top, so you have to remove the wheels to bleed the brakes, because the bleeders sit behind the wheels in front of the dust covers.
dennisonwj is offline  
Reply With Quote
Old 05-14-2018, 09:07 AM
  #4  
Mopar Lover
 
RacerHog's Avatar
 
Join Date: Jun 2013
Location: Monrovia SO-CAL (USA)
Posts: 7,044
Thanked 499 Times in 495 Posts
After looking at one of my older sale brochures, I have found that Front Disc brakes where and Option when ordering. I was thinking it was a dealer installed item. But i was wrong on that.

As for the Block.. I know it as a proportioning valve. Why are others calling it a Distribution Block? No Moving Parts inside?
RacerHog is offline  
Reply With Quote
Old 05-14-2018, 01:17 PM
  #5  
New Member
Thread Starter
 
Join Date: May 2018
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by RacerHog View Post
After looking at one of my older sale brochures, I have found that Front Disc brakes where and Option when ordering. I was thinking it was a dealer installed item. But i was wrong on that.

As for the Block.. I know it as a proportioning valve. Why are others calling it a Distribution Block? No Moving Parts inside?
I think the Distribution Block is just an avenue to hook up brake lines and route fluid, whereas a Proportioning Valve has items inside to reduce the pressure to the rear drums to "EVEN" out the brake pressure to all 4 wheels when you have disc brakes in the front and drums in the back. Several folks now have confirmed the picture I sent is ONLY a DB not a PV. This http://www.doctordiff.com/1-piece-pr...ing-valve.html is a REAL PV so they added PV capabilities to a DB, so it is an inch taller roughly than a stock DB.
dennisonwj is offline  
Reply With Quote
Old 05-14-2018, 03:54 PM
  #6  
Mopar Lover
 
RacerHog's Avatar
 
Join Date: Jun 2013
Location: Monrovia SO-CAL (USA)
Posts: 7,044
Thanked 499 Times in 495 Posts
Distribution would be for all drum brakes...
Combination Valve would be to control Disc to Drum...
So I would say that you have a Combination Valve in the photo..

Does your car have one of these by any chance?
https://www.classicindustries.com/pr...ts/md2274.html

Last edited by RacerHog; 05-14-2018 at 04:09 PM.
RacerHog is offline  
Reply With Quote
Old 05-14-2018, 08:52 PM
  #7  
New Member
Thread Starter
 
Join Date: May 2018
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by RacerHog View Post
Distribution would be for all drum brakes...
Combination Valve would be to control Disc to Drum...
So I would say that you have a Combination Valve in the photo..

Does your car have one of these by any chance?
https://www.classicindustries.com/pr...ts/md2274.html

A combination valve and a proportioning valve my research shows are the same thing.
This is a combination/proportioning valve : https://www.classicindustries.com/pr...ts/md2268.html
This is a distribution block (looks like what is in car) : https://www.classicindustries.com/pr...ts/md2267.html
This is attached to the rear axle to distribute the brake lines. https://www.classicindustries.com/pr...ts/mn1156.html

No I do not have one one of those Texas shaped valves in the brake line from front to rear, which means my car was probably a 4 wheel drum and after delivery it was made it a K-H front disc configuration but the person that did it did not add a combination/proportioning valve, nor swapped out the master cylinder to one with a larger rear reservoir to handle the extra PSI needed for the front brakes as well as fluid drop from wear on the pads and run out.
dennisonwj is offline  
Reply With Quote
Old 05-15-2018, 05:28 AM
  #8  
Mopar Fanatic
 
ZEN357's Avatar
 
Join Date: Feb 2018
Posts: 115
Thanks: 0
Thanked 10 Times in 10 Posts
I get yourself a good set of PowerStop Brake Calipers, Rotors, and pads for the front and convert the back as well to PowerStop Disc Brakes.
ZEN357 is offline  
Reply With Quote
Old 05-15-2018, 09:00 AM
  #9  
Mopar Lover
 
RacerHog's Avatar
 
Join Date: Jun 2013
Location: Monrovia SO-CAL (USA)
Posts: 7,044
Thanked 499 Times in 495 Posts
IF the master cylinder was not changed out and it has the wrong block as you suspect.... Then the system would have the wrong residual valving at least for the front caliper... That will give you a lack of pressure and a spongy long traveled pedal.

Last edited by RacerHog; 05-15-2018 at 09:04 AM.
RacerHog is offline  
Reply With Quote
Old 05-15-2018, 10:35 AM
  #10  
New Member
Thread Starter
 
Join Date: May 2018
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by ZEN357 View Post
I get yourself a good set of PowerStop Brake Calipers, Rotors, and pads for the front and convert the back as well to PowerStop Disc Brakes.
I may go to those later, want to get the car safe enough for the summer. Thanks.
dennisonwj is offline  
Reply With Quote
Old 05-15-2018, 10:37 AM
  #11  
New Member
Thread Starter
 
Join Date: May 2018
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by RacerHog View Post
IF the master cylinder was not changed out and it has the wrong block as you suspect.... Then the system would have the wrong residual valving at least for the front caliper... That will give you a lack of pressure and a spongy long traveled pedal.
I think that is exactly how it feels, it will stop, but you need lots of room in front of you. I am going to spring and just get the device I KNOW is a proportioning/combination valve. Very little money to spend to ensure my wife's safety. This is her car really.
dennisonwj is offline  
Reply With Quote
Old 05-15-2018, 03:09 PM
  #12  
Mopar Lover
 
RacerHog's Avatar
 
Join Date: Jun 2013
Location: Monrovia SO-CAL (USA)
Posts: 7,044
Thanked 499 Times in 495 Posts
Keep us posted on what works and what you find out...
RacerHog is offline  
Reply With Quote
Old 05-15-2018, 03:13 PM
  #13  
New Member
Thread Starter
 
Join Date: May 2018
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by RacerHog View Post
Keep us posted on what works and what you find out...

I will. Thanks to all of you for your guidance and help. I am ordering parts tonight.
dennisonwj is offline  
Reply With Quote
Old 05-15-2018, 08:33 PM
  #14  
Mopar Lover
 
Join Date: Apr 2011
Posts: 4,269
Thanks: 0
Thanked 381 Times in 376 Posts
bleeder screw should be on top so the air can be bleed out
TVLynn is offline  
Reply With Quote
 
 
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
61 Fury
General Technical Questions
4
03-14-2016 05:50 PM
dazzlesa
C-Body
5
03-15-2013 04:32 PM
fastbackford351
Chassis, Suspension, and Brakes
5
01-13-2012 07:29 PM
MoparMan76
Do-It-yourself Section
1
01-14-2011 02:31 PM
oldrustycars
B-Body
12
03-28-2010 11:03 PM


Thread Tools
Search this Thread
Quick Reply: Brake Questions - Help


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.