master cylinder

Did you bleed the master cylinder befor you put it on?Make sure that the booster isn't missing and parts and that the pushrod is in the slot.Check the pedal linkage and make sure the rod and pin is right, also make sure the rod it the right length.You hade to pump the master cylinder to bleed the brakes, right?So the master cylinder must be working other wise I don't think it would pump at all.I just put manual brakes on, and stoping is fine, so if your pedal is going to the floor something isn't getting fulid.

Yea thats the master cylinder. It happened with my friends GMC. Everything was bled perfectly but still had to push down like crazy to stop, and like u said it was shooting fluid up through one of the holes. We replaced it and it was like new.

Hmm, unbolt the master cylinder and put some fulid in it and have one of you get a rod or screw driver and push the plunger in the back and see if fulid comes out both holes.If not then plug the holes and see if any fulid leaks out the back of the cylinder.

Well it sure is looking like the master cylinder.I never had on go bad, but I guess if you leave them sit around the seals could go bad.

You still have air in the lines.

I believe you emailed me this also.

You have air most likely in the rear calipers still. Get a pad spreader (or make something work), remove the caliper from the axle mount, invert and bleed. Do that on both sides until you get the air out. Then remount the calipers and bleed the entire brake system from farthest to closest wheel.

Couple of off the wall suggestions. I have had air get in the master when I took the bench bleeder setup off, so I jacked the rear of the car up to level the master cylinder, and bleed the mess again. Helped a lot.

Pushrod length is important too. Too short, and you have little brake action, too long, and it locks them up.

Here's some brake bleeder help...

Garden Sprayer Pressure Bake Bleeder

1 each pump type garden sprayer, 1 - 1 ½ gallon capacity (size doesn’t matter much, it just has to be cheap and small enough to be easy to work with)
6-10 feet 3/8” clear plastic tubing
1 each ¼” brass pipe tee
1 each ¼” pipe to 3/8: hose adapter
1 each pressure gauge 0-60 PSI or so – all you’ll ever need is 5- 10 PSI, so the gauge range doesn’t have to be high.
1 each large rubber stopper – this is the hard part to find. It may take some searching to find one that is a snug push fit to the inside of the filler port on the master cylinder. You can use silicone rubber to seal a brass fitting to an old master cylinder cap, but they tend to leak too much.
Home Depot or Lowes has some ¼” brass pipe stock that is continuously threaded in the electric lamp repair department, along with the brass nuts that go with it. This is better than a pipe nipple, since the nuts can be used to secure the pipe in the cap or stopper.
OR if you can’t find the threaded pipe stock,
1 each ¼” nipple, 1 ½”- 2” long

The rubber stopper needs a hole drilled in it for the ¼” pipe nipple or threaded pipe stock. After you drill the hole, use some silicone gasket sealer to seal the pipe nipple as you push it into the rubber stopper. If you used the threaded pipe stock, use the nuts to secure the stock into the stopper.

If you can’t find a suitable rubber stopper, an old master cylinder cap can be used. Drill a ½” hole in the center for the pipe fitting. Cut the brass pipe stock to about 1”- 1 ½” long, the exact length isn’t too important. Push it through the hole in the master cylinder cap and thread one nut on top of the pipe stock where it sticks though the cap. Put another nut on the other side of the cap to lock the pipe stock in place. Apply some silicone rubber gasket sealer to both sides and when it is dry, screw the ¼” pipe that sticks out of the top of the cap into the tee.

Remove the sprayer hose and wand from the garden sprayer. You may find it easier just to cut the sprayer hose off short and connect it to the 3/8” plastic tubing. The idea is that the 3/8” tubing connects to the pickup tube inside the sprayer in a reliable, leak proof fashion. Another alternative is to remove the spray nozzle from the end of the spray wand and connect the 3/8” tubing to the wand. This leaves the hand valve in place and may be useful to start/stop the flow of brake fluid.

The 3/8” plastic tubing connects to the pipe tee using a push on hose barb type adapter. The pipe tee has one port for the gauge, one for the 3/8” hose and the other to connect to the rubber stopper or master cylinder cap that you modified.

Fill the pump sprayer with a quart of brake fluid. Set the garden sprayer on the ground and screw the pump handle down tight, and pump until brake fluid fills the plastic tubing. Then put the modified stopper or master cylinder cap on the master cylinder and pump slowly to make sure that nothing leaks or pops loose. No leaks, continue pumping until you get 5-10 PSI. Put a 6”-12” length of clear plastic tubing on the bleeder ports. Then open the bleeder ports on the wheel cylinders one at a time and bleed until the bubbles are gone. I use a 2 liter soda bottle with a coat hanger to catch the fluid . DO NOT REUSE THE OLD BRAKE FLUID. Repeat the process until you have finished all 4 wheels. You will have to pump the sprayer several times to maintain the 5-10 PSI needed to do the job. When finished bleeding, loosen the pump handle to relieve the pressure, remove the stopper/modified master cylinder cap and test the pedal.

couple things to think about,did you upgrade your propotioning block,the valve in the block could had slid to one side an no letting the presure balance out,another thing i have ran into is that a caliper might be stickin of froze up on you,you will still get good fluid out of it but the piston can't push all the air out of it! good luck!

What Prop Valve did you use? I am In the middle of doing a new M/C and would love to know.

well I have to do the 3 to 2 port conversion but can't find a Prop Valve that converts it. any ideas who makes the conversion?

in this article he has the prop valve I need but i can't find a part# or find it on fords site.

http://www.mustangcentral.net/tech/brake.html

Found it it's off a 94' Cobra.

As Ralph Wiggum says in The Simpson's "I'm Lernding"

LOL Thanks man I appreciate the info.