[sooner94]

Tackled my front brakes this thanksgiving, didnt turn out as planned. Changed calipers and pads on both sides, bleed system muliple times. After brake change the petal goes to the floor with the motor started I cant even pump it to build pressure, with motor killed i have a hard pedal.....Any Ideas?

 

[TheUnforgiven]

did you let the master cylinder run dry while you swapped out the calipers?

 

[sooner94]

No, I made sure I didnt make that mistake. Almost Pos that its not air in the lines. Ive bleed multiple vehicles before and never had trouble. I dont know where to start??????

 

[TheUnforgiven]

did you gravity bleed the calipers before doing the pressure bleed? were you sure that the bleeder was closed before the pedal was let up?

check over the entire system for other leaks. i've seen vehicles blow rear lines and wheel cylinders while bleeding the front brakes. they are two seperate systems. while you don't feel you're applying full force to the pedal, the rear brakes will still get full pressure when you're bleeding the fronts.

 

[sooner94]

I did not gravity bleed the new calipers. I did pull the back drums off and check the cylinder no leaks on either side. I dont think its a leak somewhere because the pedal will pump up hard and stay that way with the truck off. Correct me if im wrong but that "proves" the system is sealed??? No leaks

 

[TheUnforgiven]

you got air in the system. i'm betting on it.

if it was fine before, and is fubar now, i put $5 you got air in the lines.

gravity bleed it, all 4 corners. RR, LR, RF, LR, in that order. 5 minutes per corner. then pressure bleed it at all 4 corners.

unless your MC decided to take a shit, but i doubt that.

 

[snookgetter]

were you sure that the bleeder was closed before the pedal was let up?

:stupid

 

[sooner94]

Positive bleeder was closed. How do I check the Master I know my booster is ok because It will hold a vaccum after the motor is killed. Im at a lose on bleeding, never have I had a problem like this. Other than air in the system does anyone have any idea, something has changed, brakes worked fine before the new calipers. I have to be overlooking something

 

[snookgetter]

Their is a left caliper and a right caliper, you put them on the correct side?

 

[sooner94]

didnt pay attention. lol OMG would it make a difference? Will they even go on the wrong side?

 

[Brionco]

You can put them on the wrong side and that puts the bleeder at the bottom

 

[snookgetter]

You can put them on the wrong side and that puts the bleeder at the bottom

I know this is bad but cant remember why....:scratchhe

Maybe it sucks when its upside down instead of pushing fluid out...

 

[TheUnforgiven]

I know this is bad but cant remember why....:scratchhe

Maybe it sucks when its upside down instead of pushing fluid out...

no, air floats. that's why the bleeders are supposed to be at the top. air is gonna end up on the high spot of the component.

OP make sure you got the calipers on the correct side.

 

[Daves 88']

I did not gravity bleed mine though, I tried to bleed mine for 2 weeks straight and wasted 2 bottles of brake fluid before I gave up, and let my mechanic do it the right way. :doh0715: I should have tried the gravity bleed. I've done other brakes too, but this Bronco would have nothing of my normal methods.

 

[JKossarides]

Any issues with the proportioning valve below the power booster near the firewall, check the fittings for tightness....?

Usually when the pedal goes right to the floor it's the MC loosing pressure where the O ring on the piston insdie is worn and fluid passes over it.

If it's not the calipers mounted incorrectly then I would pull the master cylinder and "bench bleed" it and see what happens then re-bleed the system using TheUnforgven's sequence or Haynes Manual otherwise it might need to be replaced.....:doh0715:


Let us know how it turns out!


Good Luck ~ :thumbup

 

[sooner94]

Thanks a bunch guys..... with your help i got it fixed this morning. Parts house gave me two right calipers. Bleeder screw was on the bottom on the left side. Cant believe i didnt notice that. KISS. put my old caliper back on, had a hard pedal even before i bleed the system. Ill be taking it back next week. Just sucks to have to start over again, o well its fixed. Thanks alot maybe this post will help someone in the future that makes my ignorant mistake.

 

[Bruno2]

Cool deal! Glad its fixed.

You can put them on the wrong side and that puts the bleeder at the bottom

I battled with this when I did mine 6 mos ago. I usually just hold a caliper up to the rotor and there is usually a difference. Its hard to see the difference on Ford if you dont know what are looking at. I went and consulted with my veteran mechaic neighbor. He explained the air theory , so I got them right. The clutch slaves for the ZF5 tranny's are hard to bleed while on the truck. Most of the time the clutch line has a snake in it that makes it next to impossible to bleed on the truck.

 

[TheUnforgiven]

great news! thanks for letting us know the fix. many don't, and leave people in the future going "wtf did you do?!" :thumbup

 

[Moze]

TheUnforgiven please explain gravity bleeding not familiar with this method?

 

[Bruno2]

Gravity bleeding is simply opening up all of the bleed valves. While doing this keep an eye on the MC so it doesnt run dry. You are just letting the fluid fill the lines w/o any pressure assistance. After you run a pint out of everything then close the bleed screws. Bleed like normal starting with the farthest bleed valve from the MC. This will be the RR. Then go to the LR-RF-finishing with LF right underneath the MC. Sometims I do the bleeder on the equalizer block too.