brake bleeding
Thread Starter
Instructor
Joined: Mar 2005
Posts: 156
Likes: 2
From: collingswood nj
Dan
Thank you so much for that reply
It appears i have a bad porportion valve i didnt notice before but my dash brake light is on and i get no fluid to the front and the front is where i replaced the hoses. I dont have access to dry compressed air is there ant other way to unstck the valve or does it need replacing.
Thank you so much for that reply
It appears i have a bad porportion valve i didnt notice before but my dash brake light is on and i get no fluid to the front and the front is where i replaced the hoses. I dont have access to dry compressed air is there ant other way to unstck the valve or does it need replacing.
Pro
Joined: Nov 2010
Posts: 602
Likes: 32
From: Old Bridge, NJ
Before you replace that proportioning valve, did you confirm that when you remove the line/fitting from the front master cylinder reservoir that you get fluid flowing out there? If you do then it is your proportioning valve. If not, then it is the MC needing bleeding (or less likely, bad).
Thread Starter
Instructor
Joined: Mar 2005
Posts: 156
Likes: 2
From: collingswood nj
Yes i started to loosen the front line from the MC and i started to get fluid at the tightening screw so i tighted the line back up when makes me believe its the valve guess there is no hope to unstick it is there any thricks to replacing it
Burning Brakes
Joined: Feb 2011
Posts: 849
Likes: 0
From: Woodland California
It's no enough to have fluid in the line.
It has to squirt when you step on the pedal.
Loosen a front and read bleeder valve and have someone step on the pedal.
This should recenter the valve.
Tighten both before pedal is released.
Ralph
It has to squirt when you step on the pedal.
Loosen a front and read bleeder valve and have someone step on the pedal.
This should recenter the valve.
Tighten both before pedal is released.
Ralph
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Sometimes if you leave the rear calipers open you can get the front to build enough pressure to move the valve back,you might try pinching both new rubber lines off.
Otherwise if worse comes to worse and since you don't have dry air you might have to rig up a way to use the master cylinder pressure to apply pressure to the front side of the combo valve.
Thread Starter
Instructor
Joined: Mar 2005
Posts: 156
Likes: 2
From: collingswood nj
Have not been able to get the porportion vavle to unstick. Have decide to replace brake lines vavlve and MC. Have removed all the old parts just placed a order with wilcox for all the new parts then i hope i have brakes.
Burning Brakes
Joined: Jun 2006
Posts: 1,148
Likes: 5
From: South Dakota
Here is how I did it on my '69.
Fill the master cylinder with brake fluid, open the right caliper bleeder. Go have breakfast. Close the caliper valve and fill the master cylinder. Open the left caliper valve and go have coffee. Close the valve and open the right valve again. Fill the master cylinder and watch for a bit until you see brake fluid coming out of the bleeder valve. Close and repeat for the left side. Close the valve and fill reservoir. Now get your wife to help pump and bleed the brakes. Just jiggle the pedal a little bit now and then. It helps get some air out.
Fill the master cylinder with brake fluid, open the right caliper bleeder. Go have breakfast. Close the caliper valve and fill the master cylinder. Open the left caliper valve and go have coffee. Close the valve and open the right valve again. Fill the master cylinder and watch for a bit until you see brake fluid coming out of the bleeder valve. Close and repeat for the left side. Close the valve and fill reservoir. Now get your wife to help pump and bleed the brakes. Just jiggle the pedal a little bit now and then. It helps get some air out.
Drifting
Joined: Apr 2007
Posts: 1,970
Likes: 45
From: Cameron Park CA
However, everything I've ever read or seen or watched says you don't start bleeding the front brakes whatever method you use, power or gravity, but you start with the line that is furthest from the master cylinder which on my 76 is the right rear and bleed it until no bubbles come out.
When I bought my stainless braided flex lines from Corvette Stainless Steel Brakes, Inc., the tech there said it makes sense to bleed the FRONT system first as there is plumbing to trap air and once that is done, you have a solid system in the front of the master cylinder to support the rear piston as you bleed that part. I followed that method and bled the brakes faster than ever before.
Even in 1969 the factory Service Manual perpetuates the myth of starting at the right rear brake when bleeding the brakes. In a split system like we have, that is not necessary.
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Thread Starter
Instructor
Joined: Mar 2005
Posts: 156
Likes: 2
From: collingswood nj
Thanks for every bodies help to this point . I order all my new brake parts and a lot more from wilcox becase the web site showed everything in stock well dont allways believe everything you see . My order shipped i got it ,it wasnt complete because the proportional valve was back ordered am i wrong or do you think i should of been told that when my order was shipped here i was waiting on my parts and was never told it was back ordered untill i called .
Intermediate
Joined: Mar 2004
Posts: 26
Likes: 0
From: Ojai CA
This has been covered about as well as you can expect but I have one little addition. I use a mighty vac but don't use the hand pump. I simply put a long hose on the manifold vacuum connection, run it though the container, connect to the bleeder valve, start the car and open the valve. Easy peasy. One man job.
