[zipchip]

I have read a few posts (search) on this issue but not sure what applies to a 1970, so need yr help.

First,this is a full resto, reconditioned, but all original components and new steel brake lines....I cannot get brake fluid to the back drums. I assume the proportion valve (cleaned) is the culprit and somehow needs to be reset or adjusted.

I am using a hand bleeder vac pump that pulls the air and fluid out. I also tried it w/o the bleeder pump, same result. Front disc's bled out just fine. Thanks.

 

[danhalt]

Can you bleed fluid before and after the rear hold off valve?
I had trouble with mine when starting with a dry system. It didn't allow any fluid to go past the hold off valve.
Or as you mentioned to make sure your front distribution block valve is centered.

 

[warped]

You should have started with the brake farthest from the master,passenger rear when doing all new lines.
After you get fluid there the rest are a breeze.

 

[Bubba's 69]

Gravity bleed.....I never had luck with a vacuum pump.

I always let them gravity bleed first. Start at the RR go to the LR then RF and lastly LF.

Let the fluid run out of each untill the bubbles are gone. Then do the two person method a couple times if there is still air.

Has the master been bench bled?

 

[danhalt]

If your dash brake light is staying on the valve in the forward distribution block could be off center and needs to be reset.
One method of reseting is to open both front bleeders and jamb the pedal as hard as you can.
This can recenter the valve for you. or you can remove the line that goes to the rear brakes from the block and push the valve back to the center.
Again if you are using a new rear hold off valve try bleeding before the valve and after. Theres problems with these new valves.
Good luck

 

[1badss396]

Its no fun but once you get it to the first brake line it will be a lot easier to do. No matter how much you use the vacuum pump it will always get some air.