brake bleeding isues

I'm trying to bleed my brakes but when someone pushes on the brakes and I release the wheel cylinder valve nothing happens. I get no fluid and the brake pedal doesn't go to the floor. What am I doing wrong.

 

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It would sure eliminate a lot of questions if you would give us some history..

 

The master cylinder is new the wheel cylinders are new. When I remove the brake line from wheel cylinder the fluid shots though just fine. What would block the fluid from going though a new wheel cylinder.

 

After further investigation I've narrowed it down to the master cylinder. It comes to a complete stop about 3" from the floor and fails to put the needed pressure on the fluid to stop. There are no obstructions preventing the pedal from going to the floor. the problem is within the master cylinder and it's brand new. What did I do wrong and how do I fix it.

 

Does your master have dual reservoir or is it like the original early model. Single line coming out or two of them?

 

The master cylinder is a dual with two lines and a proportioning valve. I don't know a lot about proportioning valves but I was wondering if that could be the reason that I can't push fluid out a wheel cylinder valve one at a time. If so what's the solution, would I have to have my lines blead by a by a macnine.

 

Rookie response here but I thought early cj5's didn't have a proportioning valve, but used a larger front brake wheel cylinders to help increase front braking. Something like 7/8 bore in the rear and 1 1/8 bore in the front.

 

thinking you have a stopped up bleader valve, maybe wasnt drilled far enough from the factory. either that or your push rod is adjusted to tight not letting the MC come all the way back to the top of its stroke..........

 

With the dual master cylinder (split front/back) (or diag frnt-left/rear-right) the two pistons operate independent from each other. If the front piston is supplying the front wheels and there is no leak, the pedal will not go all the way to the floor.

 

I think that is exactly what's happening. The master cylinder is split front and back and there are no leaks. I haven't tried to bleed the fronts yet but when I try the backs independent of each other the pedal stops about half way down. So if a dual master cylinder won't let you bleed the wheel cylinders independently how do you do it, or do I have to take it somewhere and have it done.

 

do one end then the other.

 

You posted that if you take the line off the wheel cylinder, fluid will shoot out. If the line is back on and the bleeder valve removed and you cannot get any fluid out then you have a problem with the inside of the wheel cylinder. I suspect the rod that goes into the piston is miss-aligned on one side and is pushing the piston and cup too far in and blocking the feed hole. Either that or something plugging the feed hole.

 

That's what I'm seeing. If you open a bleed valve on each end of the Jeep, the pedal should go to the floor.

That's what the dual master cly does. If you have a failure on one end, the other end is still there to stop you.

You could use one of those vacuum pumps and little containers and suck the air out of the system. That way you don't have to mess with the pedal. Harbor freight and others have them.

 

I use a very simple (one man) system to bleed my brakes. Got 5' of clear plastic hose from H-Depot (used for water dripers) and loosen the bleeder about 1/4 turn. Push the tubing over the end of the bleeder head. Place the other end into a clear jar and put enough brake fluid in the jar to cover the end of the tube. Fill master reservoir. With the jar placed where I can see it, then slowly push peddle down and observe the air bubbles in the jar. When you let up on the peddle, the fluid from the reservoir goes into the master plunger and since the tube is in the fluid in the jar, it can't suck any air back up the tube. Several times on cycling the peddle and you will see no more bubbles in the bottom of the jar. Keep the master reservoir full at all times. When no more air is present, finger tighten the bleeder screw and remove the tube then snug down bleeder screw with wrench. Move to next wheel. I pre-adjust shoes before bleeding. With the 5' of tubing you should be able to have the jar visible for all 4 wheels. It's a one man show.

 

I'm at my wits end, I tryed the fronts today with the same results. The pedal goes half way to the floor and comes to a dead stop. All the wheel cylinder can't be pluged The problem has to be in the master cylinder which is brand new and I have hard time believing or the proportioning valve which worked fine before the brake system rebuild. There is nothing blocking the pedal from going to the floor, it has a clear path.
Whenever I've blead brakes in the past, and released the bleeder valve, the pedal always went to the floor. I need help before I have to admit defeat and take it to a brake shop.