Front brakes will bleed fluid but, won't stop

[Broncobowsher]

I see new master cylinder. Did you get the pushrod length (booster to master) set right?

 

[chrisd0729]

I see new master cylinder. Did you get the pushrod length (booster to master) set right?

I think so. I had to extend it about 1/2" for the new MC. I made little adjustments extending it out until I could feel it bottoming out in the MC as I held it up against the booster and then backed off 1/4 turn. I didn't adjust based on pedal height as I read that bottoming it out into the MC would make the brakes drag like you're riding the brake.

 

[gr8scott]

These pages copied from the 1976 Ford service manual may help out with what Paul and Steve described.

Thanks for posting that Master Chief.
On the second page it states:
"On vehicles equipped with disc brakes, the metering valve must be pulled
outward as shown in Fig. 12. This is to allow brake fluid to reach the
caliper assemblies. This operation is particularly important if pressure
bleeding equipment is being used."

So what does it mean if brake fluid reaches the calipers without the metering valve pulled? I recently bled
my brakes without pulling it and they both seemed to bleed fine.

Edit: Sorry for hijacking your thread Chris.

 

[bigmuddy]

Post a picture of your caliper.

I had the same problem as you and swore up and down they were mounted correctly because bleeders were on top. Nope had to eat a lot of crow....

Swapped them side to side and bingo, fantastic brakes with little bleeding. If you are getting white looking fluid, you still have air in the system and with the calipers on the wrong side you will never get all the air out even with a mity vac.

 

[5001craig]

Post a picture of your caliper.

I had the same problem as you and swore up and down they were mounted correctly because bleeders were on top. Nope had to eat a lot of crow....

Swapped them side to side and bingo, fantastic brakes with little bleeding. If you are getting white looking fluid, you still have air in the system and with the calipers on the wrong side you will never get all the air out even with a mity vac.

Me too...

 

[Broncobowsher]

Helped a buddy who was fighting the same thing. After I pumped forever I got out and inspected his work. The bleeders were real easy to access the way he put them on. He had the boxes labeled, there was now way he could have put them on the wrong side.

He had them on the wrong side.

A quick swap and we had brakes inside 10 minutes.

Until you post a picture this is what I am going with.

 

[September 1972]

All the advise so far is sound and thoughtful, there are a few points that I may add that might help.

Put a pressure gauge 0-1500 PSIG on the master I would want to see the needle jump to 800 to 1100 PSIG and hold steady to the fronts. Then check the pressure at the calipers. If the left and right calipers are the same pressure wise remove the pads and see if they feel slipperly. If they do replace them with 60 dollar Wagner mid high line pads.

Using 25 grit sandpaper surface them and using a 28 tooth hacksaw blade vent them in the pattern used on ventilated rotors. If you can gain access to both sides of the rotor use a die grinder with a 25 grit 6 inch disc and while a assistant spins the rotors kiss the rotor surface until most of the high spots are gone.

Drive it and get up to 60 and stand on the brakes to 40 and let cool for 5 minutes and do it two more times. You should smell the brakes but don't get them too hot or the resin binder will float to the surface of the pads and make them slippery.

Ford calipers and how they hang are not a great design, they have to seat to work properly and they still eat pads as you guys know. By venting the pads and coarse grinding the rotor the high temperature gasses can escape carrying the pad material inside the gas so that the pads can marry the rotor.

The proportioning valve is a delay valve only and it's pressure release point to the rears is predicated on the fronts working properly.

My brake jobs never squeak and will lock up the rotors at freeway speed which by the way, is not easy to do. Try and get the antilock fronts to activate at 70MPH, the rears should not lock up at that speed under any circumstance.

 

[chrisd0729]

Here are the pics of current install - drivers first, then passenger side.
Look correct?

 

[chrisd0729]

just checking in - do these pics look like calipers are installed correctly?

 

[Broncobowsher]

They are correct.

 

[DirtDonk]

Unfortunately... Yes.

The caliper hoses always bugged me with the way they mounted though. I always thought the little shoulder should go against the caliper and act to keep the fitting from twisting when tightening down the bolt. But if I remember at least some calipers are cast in such a way that there is no way to fit the hose that way.
Is that what you found with yours? I see in the first pic that the shoulder is facing away from the caliper, so it made me wonder about that.

Otherwise, your calipers look correctly oriented and the anchors look correctly installed.
I do see that things look totally dry however, and the sliding surfaces should always be lubricated with brake grease or anti-seize. Contrary to popular belief these days, caliper grease is not intended for anti-squeal duties. It's a lubricant that is there for the sliding surfaces only. They sell the anti-squeal compounds that solidify and don't risk migrating to the friction surfaces like a moly-lube stuff could.
However, it does seem to work as an anti-squeal product for many people. I just wouldn't ever put lubricant on the back of pads myself. So wanted to at least throw out the PSA rant when I had the chance.

In your case though, even though things are so clean and new that it's hard to believe that it might be an issue, I would still pull them off, dress the sliding surfaces with a file to make sure they're smooth, level and free of rust or anything else, then lube them up with the proper stuff and put them back on.
You never know... Perhaps your calipers are sticking just enough to create an issue.

Worth a shot at this point.

Paul

 

[Steve83]

The fine red powder on each of the upper slides shows that there's no grease on them, and that they're rusting & wearing. You should do as Paul suggested, and fix that ASAP. Any of these greases is correct:

 

[bigmuddy]

Back to the grease

 

[73azbronco]

My bet is no pressure to front because of master cylinder not working right or pushrod depth not set right. That style caliper never impressed me, but it works, and works rusted or otherwise with a thousand pounds of pressure moving that caliper in the groove. You have that caliper/brake pad tapped right against the disk right?