No brake pedal pressure


bowtieboy12
05-26-2009, 05:25 PM
'99 ZX2 - the brake pedal goes to the floor with no pressure or resistance. the brakes still work but you gotta really stand on the pedal, like air brakes feel or when you blow a brake line. all the lines are fine with no leaks. i think the rear shoes are way outta adjustment b/c when you press the pedal you can hear them take a second then smack the drum. from what i've been told this is where the pedal pressure comes from. the problem is that this is a POS ford and has no external adjuster and i cant get the drums off the hub b/c they are pretty much fused on by rust. (there is supposed to be a threaded hole on the drum to put a bolt through to push off the drum but thats a no-go) i've also pondered whether it could be the power brake booster???? if anyone has any ideas suggestions or miracle cures i'd really appreciate it. thanks guys...

rhandwor
05-26-2009, 07:58 PM
The Fords I worked on with drum brakes on the rear either had a rubber plug or hole on the back. Use a brake adjuster and tighten them up so the shoes just start rubbing.
Next bleed the brakes to remove any air in the system.
If this doesn't work replace the master cylinder.

Davescort97
05-27-2009, 05:27 AM
Your zx2 rear brakes are way out of adjustment, like you say. You have to get the drum off to adjust them. Spray some penetrating oil around the lugs and let soak overnight. Whack the drums at the bottom with a big hammer to break them loose, then put a 13 mm bolt in the threaded drum to pull it off if needed. Probably won't.

There is a cam between the shoes on the top half of the backing plate. It is located on the parking brake actuator. Stick a screwdriver into the cam and adjust the brakes until the drum goes on with a little friction. Check for worn parts. Shouldn't make noise when you brake. If you have broken parts it could be a dangerous brake problem. Repair ASAP.

AzTumbleweed
05-27-2009, 07:05 AM
Just for the heck of it apply the hand brake then push the pedal. If there is a noticeable improvement then it's an adjustment. First thing that crossed my mind was the brake booster. Try pressing the brake pedal with the engine off and see if it's the same as when running.:2cents:

denisond3
05-27-2009, 10:06 AM
To get the drums off my Escort, I heated the drums with my acetylene torch - right close to the center hole; along with banging sideways on the drum surface, and tapping fairly hard agains the back edge of the drum. Its just to get the drum started off of that hub - where the hole in the (unrusted) drum is -exactly- the same diameter as the unrusted raised part of the hub. The screw threads in the side of the drum to help with drum removal had already been stripped out on my drums. Before I put the drums back on I lightly filed the hub and the center hole in the drum.
The couple of times I have had the pedal go to, or close to the floor - it was failure of one half of the dual brake system. If the failure was in the master cylinder, the only place you might see brake fluid, would be on the inside of the vacuum line from the booster to the intake manifold.
Once though, the car had been sitting for a couple of weeks, and one side of the master cylinder was empty. The brake pedal went almost to the floor, when the other half of the brake system would still stop the car. It took a lot more pressure though. It was due to a brake line with a pinhole in it, up beside the fuel tank. After filling the m.c. reservioir and holding the pedal down with the engine running, I was able to see the brake fluid getting the line wet underneath the car, but I didnt locate the actual leak in the line until I pulled the line out - and replaced it.

rhandwor
05-27-2009, 05:22 PM
Auto Zone and Advanced Auto have loaner tools. Pep Boys also have them .
http://www.autopart.com/tools/toolsmain/tool/T_8050.htm They look like this Northern Supply also handle them.
This will pull a drum but may damage some hardware.

mightymoose_22
05-28-2009, 08:17 PM
I agree, the first step is to pull the drums and have a look at the brakes. Adjust if necessary.
However, did you recently do any brake repair?
If the symptom just suddenly started then I would instead focus on the booster and master cylinder.
A simple check before you take anything apart is to verify vacuum is getting the the booster and listen for leaks from it.

Add your comment to this topic!