Cj7 - replacement master cylinder bubbles - Page 2 - JeepForum.com

Reply
 
LinkBack Thread Tools
post #16 of 21 Old 08-22-2013, 11:08 PM
Skerr
Registered User
1985 CJ7 
 
Join Date: Sep 2008
Location: White Springs
Posts: 9,495
Quote:
Originally Posted by wellmax View Post
one time I when through 2 or 3 rebuilt master cylinders on my 1984 cj with power brakes, before I got one that worked properly.

I was using advance auto, I would just take them back and they got me another one.

I bench bled the master cylinders using the inserts and short tubes provided with each kit. used the handle of my ratchet or screwdriver to pump the master cylinder, had to make many pumps until the bubbles stopped.

then installed the master cylinder and all was good,
once I got a good master cylinder.

brakes on a old jeep are marginal at best, power brakes make it much better.
I had this similar problem with Auto Zone masters. I have read where several of the guys went through this as well. Wish we still had the old days when you could buy a rebuild kit for $3 and do it yourself!

Quote:
Originally Posted by Msmall View Post
I do need to do the power brake upgrade. Part of the reason I've put the minor bubbling on the back burner.

I also want to k so what is going on with this. It seems like when the brakes are engaged and the rod is pushed into the master that it is forcing air in. As it e rod is catching air when out and then pushing air in when engaged.
Your concept is good, but one of the steps in bleeding a master is to make sure it is level. That's where a vice and a level come in handy. I suppose it is to ensure bubbles aren't trapped in pockets inside the body. Wipe the master off really well, depress your brake pedal slowly to avoid squirting, and watch for leaks. If your plunger is grabbing air you will be losing fluid at the rear of the master. It could be running down the inside of your firewall as well as outside. If you don't have evident leaks then I think you should try bench bleeding again. Use shorts strokes on the master, not long ones (don't know why, just what the directions say to do!). You could really use a second set of eyes, if you don't already have them. It takes a LOT of strokes to get the air out.


Kerrdog
Go Fish! <*////><

But the right word at the right time... "Hey, give me a little hug!" That's the difference between lightning and a harmless lightning bug!
Skerr is offline  
Sponsored Links
Advertisement
 
post #17 of 21 Old 08-22-2013, 11:15 PM Thread Starter
Msmall
Registered User
1986 CJ7 
 
Join Date: Jul 2013
Location: Fairfax
Posts: 105
This master was refurb from auto zone...I'm convinced its bad. The amount of air that is bubbling is significant and seems to be pushed in then it fully escapes. This repeats with the same amount of air.

I'll get into is weekend/early next week. But I could just do the power brake upgrade. It tough toget a solid answer as to what part are involved in the power upgrade.
Msmall is offline  
post #18 of 21 Old 08-22-2013, 11:21 PM
Skerr
Registered User
1985 CJ7 
 
Join Date: Sep 2008
Location: White Springs
Posts: 9,495
Are you talking about pulling a brake system from the junkyard, or purchasing a new unit?

Kerrdog
Go Fish! <*////><

But the right word at the right time... "Hey, give me a little hug!" That's the difference between lightning and a harmless lightning bug!
Skerr is offline  
post #19 of 21 Old 08-23-2013, 12:06 AM
CSP
Registered User
 
Join Date: Aug 2002
Location: Colorado
Posts: 15,937
Quote:
Originally Posted by Msmall View Post
I'll get into is weekend/early next week. But I could just do the power brake upgrade. It tough toget a solid answer as to what part are involved in the power upgrade.
You realize that braking systems aren't that simple, right?

Have you searched at all or do you just want someone to answer your particular thread and not look anywhere else?

Some "light" reading on the subject: http://www.pirate4x4.com/tech/billavista/Brakes/
CSP is offline  
post #20 of 21 Old 08-23-2013, 12:26 AM Thread Starter
Msmall
Registered User
1986 CJ7 
 
Join Date: Jul 2013
Location: Fairfax
Posts: 105
Quote:
Originally Posted by Skerr View Post
Are you talking about pulling a brake system from the junkyard, or purchasing a new unit?
I'd purchase new or a refurb
Msmall is offline  
post #21 of 21 Old 08-23-2013, 12:32 AM Thread Starter
Msmall
Registered User
1986 CJ7 
 
Join Date: Jul 2013
Location: Fairfax
Posts: 105
Quote:
Originally Posted by CSP View Post
You realize that braking systems aren't that simple, right?

Have you searched at all or do you just want someone to answer your particular thread and not look anywhere else?

Some "light" reading on the subject: http://www.pirate4x4.com/tech/billavista/Brakes/
yes I've researched and have looked all over which is why I said it is difficult to find exactly what is needed in terms of parts and instructions to go from my current setup to power brakes. There are many opinion and a definitive answer isn't around.

I've heard, just the booster is needed, just a booster with a diff master, booster with same master but a bracket, booster diff master new line, booster new master new lines and new prop valve, even read new wheel cylinders
Msmall is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com 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 e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 Off
Pingbacks are On
Refbacks are On

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