Sqishy Brakes...hardly work

[Awagner]

ive had soft or spongy brakes on my 93 xlt for as long as i can remember but today i hopped in to go get lunch, and about rolled through a couple of stop signs, the pedal goes almost all the way to the floor and then barely starts to stop the truck, i cant lock up the wheels, which i thought would be some sort of brake line leak or something. when i pump the brake pedal with the truck off after 3 or 4 pumps the pedal is firm which leads me to think that there might be a vaccum leak related to a brake booster or something, anyone with this problem

havent had much time to look through forums too intensly cause i kinda wanna get it fixed as fast as possible

thanks

Awagner

 

[MrQ]

Probably need to bleed the brakes and check the master cylinder. Do you have fluid in the reservoir.

 

[Awagner]

i just topped off the resevior, and they got noticably better but still not dreamy

 

[mikeinri]

You may have a leak ready to explode...

Best way to test this, and this is DESTRUCTIVE, so be sure you are either ready to fix it or at least not need to drive it afterwards...

Park the truck on a clean surface. Turn the engine off. Pump the brakes until you get a really hard pedal and hold them for a minute or so. If you have a weak part (rubber lines, wheel cylinder boot, steel line ready to rust through, etc.), this should cause it to fail, and the pedal will go to the floor.

Then, just trace the puddle of brake fluid on the ground to the source of the leak and fix it...

Hope this helps.

Mike

 

[MrQ]

Spongy brakes usually indicate air in the lines. I think you would be better off bleeding the brakes than what mike suggested. That's a last ditch effort IMO.

 

[YBCold]

i have similar issue. i have a puddle under my car up near what i think is the HCU but i hear bleeding it "requires an expensive tool" has anyone tried this? i probably will have to bleed my master cylinder too and the rest of the system but can it be done?

 

[shaggymane]

i have similar issue. i have a puddle under my car up near what i think is the HCU but i hear bleeding it "requires an expensive tool" has anyone tried this? i probably will have to bleed my master cylinder too and the rest of the system but can it be done?

yeah, it's called a girlfriend. She sits in the truck and does the pump and hold on the brake pedal while you unscrew and screw the bleeder valve.
Seriously though, there's is no expensive tool needed. you've got a 91 too. I just replaced the rear wheel cylinders. Bleed them like normal

As for the OP. Pull the rear drums off and see if the self adjuster cables are intact or even there. Sometimes a previous owner will remove them.

Had an 82 f250 with a soft pedal. Friend recommend adjusting the rear brakes.
Nah, nah, it's the mater cylinder, says I. Bucks later I still had a spongy pedal. That's when I checked the rear brakes. Guess what? yep. no self adjusters. All it needed was adjusting the rear brakes.

 

[YBCold]

oh ok. ill see if the adjuster is there. but what about the leak?

im having is it normal? to me it looks like a big leak.

it would puddle under my fuel filter and then drip from there onto the pavement

 

[nitro71]

I've had good luck with bleeding brakes by myself. Take a small water bottle or other clear bottle, dry it out. Drill a hole in the lid. Get 2' of clear tube that will fit on the bleeder. Get a little box or something to sit the bottle on, it's gonna get oily so nothing nice. Fill bottle a couple inches or so with brake fluid, submerse tube in fluid in bottle, attach to bleeder. Crack bleeder barely open. Pump brakes 3-4 times. Fill up brake reseviour after EVERY pumping. Observe bottle and clear tube. Should be full of liquid with no air bubbles. Pump a few more times to be sure. If you're getting bubbles tighten down the bleeder. If you don't contaminate your brake fluid you can re-use it if you want to.