In need of advice once again

[GeorgeG]

Have your friend check the vacuum pump to be sure it's working

[LizStreithorst]

Will do.

[GeorgeG]

Diesel engine do not create vacuum that is why they need a vacuum pump. A quick check I did not find any recalls on your brakes other than the parking brake. You can always ask a Ford dealer if that was taken care of. That should be free for them to check the records. They need the VIN number to do that. Your buddy Chip can write that down for you if you do not know where it is but it is on the right hand corner looking through the windshield. Might be on the drivers door also.

Here is how "Brakes" are spelled

[Mugwump]

Are there any symptoms having to do with the break pedal?
Does the pedal go to the floor when things don't work?
Do you have to pump the brakes?
Unusual noises?
Hand break work?

The break peddle is perfect.
No noise at all the first 2 times.  Suddenly the breaks simply did not work!  Today it made a noise and vibration in the pedal when it happened.  At least that let me know that I needed to stomp all my weight on the pedal.
I have no idea about the hand break.  I never use it.  I just stick it in "park".

..that's how I knew my front bearings were going/gone.....stutter/noisy pedal....pump quick and they came back....then pump quick stopped working too....but by that time I had an appt with Steve, my mechanic, had the new wheel bearings ordered/received....I got the parts cheap from his source, then $75 per axle to replace....

[LizStreithorst]

Forgive me, George.  I'm dyslexic.  I never could spell and I will never be able to.  Learning to read was dang hard enough! Despite my shortcomings I ended up being pretty dang literate, don't you think?  It's because I found good books irresistible and made myself read because the effort I put in paled in comparison of what I got from it.  I was thought of as not real bright for most of my life, but I am smart.

I can't spell.  I have no sense of direction.  I have a bit of a problem with face recognition but I do not appreciate being made to feel stupid

[LizStreithorst]

Are there any symptoms having to do with the break pedal?
Does the pedal go to the floor when things don't work?
Do you have to pump the brakes?
Unusual noises?
Hand break work?

The break peddle is perfect.
No noise at all the first 2 times.  Suddenly the breaks simply did not work!  Today it made a noise and vibration in the pedal when it happened.  At least that let me know that I needed to stomp all my weight on the pedal.
I have no idea about the hand break.  I never use it.  I just stick it in "park".

..that's how I knew my front bearings were going/gone.....stutter/noisy pedal....pump quick and they came back....then pump quick stopped working too....but by that time I had an appt with Steve, my mechanic, had the new wheel bearings ordered/received....I got the parts cheap from his source, then $75 per axle to replace....

So many possible causes...Poor Chip will have a job on his hands diagnosing and fixing.  I'm going to have to get his email address and send a link to this thread to him.  Poor guy.  He hates break stuff because breaks get him dirty and he hates getting dirty   He is the cleanest mechanic I have ever seen!  Too bad for him.  He will have brakes to suffer though.  He will do it for me.  He's kind of a buddy.

[BillT]

You should familarize yourself with your hand brake.
It is a back-up to the normal brakes and would allow you to stop your truck if the normal brakes fail.

[LizStreithorst]

I shall, Bill.  Mine's a foot pedal break but it does the same thing either way.  I'll ll try it out when I need to slow down next time I drive the Beast.  When my brakes fail I never think of using it because I never use it

[Mugwump]

I shall, Bill.  Mine's a foot pedal break but it does the same thing either way.  I'll ll try it out when I need to slow down next time I drive the Beast.  When my brakes fail I never think of using it because I never use it

If you try it out...hold on tight...it can bite quick and send ya forward against the wheel....

[Rjb3]

If I remember correctly, to check the vacuum booster you put your foot on the brake and then start the engine. The pedal will not change if you're not getting vacuum to the brakes. If the pedal pushes your foot up, you've got vacuum. Another possibility is the vacuum is between my ears and I don't know what I'm talking about.

I'll bet Chip will know.

[Mugwump]

If I remember correctly, to check the vacuum booster you put your foot on the brake and then start the engine. The pedal will not change if you're not getting vacuum to the brakes. If the pedal pushes your foot up, you've got vacuum. Another possibility is the vacuum is between my ears and I don't know what I'm talking about.

I'll bet Chip will know.

I think you're right, Bob....I remember something like that too....

[Rjb3]

Or does the pedal go down when you start the engine? LOL

Chip will know.

[Mugwump]

Or does the pedal go down when you start the engine? LOL

Chip will know.

LOL....

note: "System Operation Test"


With the engine OFF , pump the brake pedal until the supply vacuum is entirely gone.
Put light, steady pressure on the brake pedal.
Start the engine and let it idle. If the system is operating correctly, the brake pedal should fall toward the floor if the constant pressure is maintained.

[LizStreithorst]

I just re read this thread.  The consensus is is that it is most likely the master cylinder and the second most likely thing is the booster pump.  I'll talk to Chip tomorrow.  He won't like this job that doesn't have a for sure solution and involves brakes.  (he hates brakes).  If Shiny man is still with him I'll have him make The Beast Shiny while Chip takes care of the working parts.

[JR]

If its the ABS Chip can pull up history codes. But if the ABS fails it will go back to standard brakes. In less there is a leak in the ABS unit. Is this a Hydro boost system or a vacuum boost system. If the power booster goes out the pedal should get real hard to push. Most Fords Have a one way Valve in the vacuum line to the booster that can cause a problem. Most master cylinders go to the floor when they are bad the fluid bleeds past the seals in the master. The one way valve will restrict the flow of vacuum to the booster if its bad. If it is hydro boost I would check out the hydro boost unit ford had a lot of problems with them. The first thing I would do is check my pressure at the calipers and go from there. You should not have to throw parts at this truck. We know it is not the calipers or the wheel cylinders they all dont stop working at the same time. If the pedal wants to kick back at you its in the hydro boost.If the pedal is hard I would change the power booster if it has vacuum. Don't know what system you have that van could have either one. If they both check out change the master. It is a pressure problem. That is the best I can do without driving the van. If chip is as good as you say Liz he can fix this without throwing parts at it.