Gravity brake bleed not working
Have new master, all new slaves, empty brake lines, everything is dry except for the master which I bench bled and is full of dot 5. Have slave bleed valves open down below.
No fluid will come out of the master.
Do I need to push my brake pedal down and put a wedge in to keep it down? Even when I was mounting the master after bench bleed no fluid was coming out of it before even attaching brake lines.
Kinda vague, could use some better info- year and brake type for instance; but here goes:
By "slaves" I assume you mean the wheel cylinders. So if you have wheel cylinders, I'll assume we're talking four wheel drums and not front discs. I'll also assume you've got a dual reservoir master, and not the early single reservoir unit.
The master cylinder for four wheel drums has residual valves in the MC ports that will generally keep you from being able to gravity bleed the system. In disc brake applications these will only be in the port for the rear drum brakes, not for the front discs. They can be removed, reconnect the lines and gravity bled, and then reinstalled; but that will reintroduce a bit of air into the system again. but you'll get the majority of air out.
There is also an internal transfer port in the dual master cylinders between the front and rear portiions, this generally requires the brake pedal to partially depressed (about an inch or two) to allow the fluid to gravity feed. Block the pedal in position. (This will sometimes allow it to gravity feed even with the residual valves still in place, so try this first.)
Lastly, if it's a front disc system, the proportioning valve may also be blocking flow. If it's a four wheel drum system, it should just be a distribution block and not offer any resistance to gravity flow.
Long story short: Buy a six pack and bribe a buddy to come over and pump the brakes for you. It'll be less horsing around, and it'll be done and over with.
Oh, by the way; if it's got power brakes, bleed them with the engine off. There's the potential for booster damage if done with the engine running.
