1972 Vette, new master cyl., new brake lines. Master cyl. was bench bled. Getting fluid to calipers. Pump the pedal and hold. Crack the bleeder but no fluid! Pads don’t move. Any ideas??? Thx, Bob

 

Is the bleeder plugged with Rust and Crud?

 

YES...it can be plugged bleeders.....

KEEP IN MIND that having the master cylinder as LEVEL as possible is best. regardless if you 'bench bled' it or not.

YES. You do not have enough fluid in the lines and system that will make the 'pumping brake pedal method' work.

All you are doing is compressing ALL of the air that is in the lines. You may need to pump the pedal many many times before opening up the bleeder. And if whoever is at the bleeder...they need to carefully listen for air coming out. It will be like a light 'pffff' sound.

Either keep dong this and WATCH the level of your brake fluid and see if it is beginning to go down. When you see that you are getting the level to go down. Keep doing what you are doing and the fluid will finally get there.

OR...you can take the lid off of your master cylinder and open up a bleed in the front and one in the rear and WATCH the level of the brake fluid and BEGIN the process known as 'gravity bleeding'. DO NOT let the master cylinder run dry. This may also take some time. And this method DOES NOT require you to touch the brake pedal.


When you get the brake fluid to flow. And you go back to your pump method. Shock the frame with a hammer and also the calipers due to the fact that you are startling off with a brake system that is DRY. And really small air bubbles can attach themselves to the inner walls of the lines.

So shocking the frame and caliper swill dislodge them so when the fluid stream is moving..the bubbles are going with it.

Because IF you don't. You can get a GREAT brake pedal..and then the next day the pedal goes to the floor. Do not ask me how I know this.

DUB

 

try gravity bleeding them,

open 1 corner at a time,[don't press the pedal],starting with the RR-LR-RF-LF,let it drip a few mins,then close everything up and see what kind of pedal you get

 

Using the "Pedal method" seldom works because its likely you tripped the Proportioning Valve into a blocked line mode. That's what it is suppose to do; detect a loss of pressure in the system and block off that portion. Turn on the IGN key and see if the dash brake warning light is on.

If you don't want to buy a Motive pressure bleeder or a vacuum pump then you will have to gravity bleed. It takes a while.
Click on my profile for pictures of a tool that will help you, if you insist on using the pedal method.

 

new brake lines, but did you replace the rubber sections, they can collapse on the inside and block flow as well

 

I guess I am just lucky. Mine bleed all over the ground...

 

Is the M/C actuator pin the correct length for your new M/C? If too short, you may get NO actuation of the M/C. That pin should be the SAME LENGTH as the space in which it fits (but no longer).