Brake help needed

[DirtDonk]

...could they have given me a caliper thats wrong that would bolt up but cause problems?

I'm not absolutely sure, but I don't think so. The only calipers I've seen that Ford made that bolt up to those brackets and still have the normal hose fitting are the ones for trucks. And those should all be the same.

By "wrong" the only thing I can think of that would cause something like this is a mis-matched mating/sliding surface.
If you had one with a larger piston, you'd still have a firm pedal because your 1.125" bore master should be able to push enough fluid.
By any chance are you plumbing the front reservoir to the front brakes? Or are you using the rear reservoir like original? As mentioned, some masters might have different piston flow capabilities (don't know this for sure either, but have heard of it elsewhere).

If the sliding surface is wrong, damaged, rusty, or the slider/anchors are wrong (or installed incorrectly), you could conceivably have an issue like this.
When you put all the new stuff in, did you get new hardware for the fronts too? There are different versions of the caliper anchor with it's spring that would jam up and not allow the caliper to slide on it's mounts.
How hard were the calipers to install? Did you have to really hammer the anchors in, or did they go int smooth and easy?

Paul

 

[Crush]

Sounds also like you have the master cylinder to prop valve lines reversed. The big resovior should power the front brakes. That's how mine is set anyway.

 

[El Kabong]

Kinda grasping at straws here, so I'm going to throw in any of the odd possibilities that come to mind. You may have already found it from some of the recent posts above. Some of this is probably a repeat, & some may not apply to the parts you have, but we are trying to find that one odd missing piece.

It sounds like you probably have a good master cylinder & rear brakes based on your plugged port to front brakes test. It is possible that the MC moves enough fluid to give a solid pedal with the port to front plugged, but not enough to move the calipers to engage completely, although that seems unlikely.

How are you bleeding the brakes? When you bleed the fronts, is there a good flow of fluid from the bleeders?

Have you looked at the pads & calipers to be sure that the pads are fully in contact with the rotors, not caught a little cockeyed? Nothing springy fallen between pad & rotor or caliper & pads? Calipers slide & are free to center themselves over the rotors?

Tell us about your H-block. What is it from? Some years (78-?? broncos & ?? F150s) have a pin that has to be held out when bleeding or the fronts won't bleed correctly. Some of the earlier fullsize guys have chased their tails for days before finding about the pin. There is also a routine to un-switch the brake warning light switch in an early bronco. Tom's instructions. I wonder if there might be something related to it being off centered. And as mentioned above, reversed lines to the H-block (In & out, or front & rear) could cause issues.

I don't like to do this unless the hoses are about be replaced, but an old mechanics trick is to gently use vise grips to pinch a rubber brake line. They say it is ok if you don't crush the lines, but it still makes me uneasy with brakes. And it seems like it would leave a pinch in those new braided lines. It would show if the problem is beyond or before the hose. So if you have a solid pedal with both front hoses pinched, you would know if the issue is in the calipers. Brakes still spongy would send you looking upstream. Do you still have the old hoses? It might be worth swapping them back in to test if you don't find it otherwise.

If you could post pics of the H-block, calipers, MC, hoses, etc. it might help to figure it out. Sometimes seeing the actual part instead of picturing possibly different parts from memory will help find the problem.

 

[KBUCK1]

Kinda grasping at straws here, so I'm going to throw in any of the odd possibilities that come to mind. You may have already found it from some of the recent posts above. Some of this is probably a repeat, & some may not apply to the parts you have, but we are trying to find that one odd missing piece.

It sounds like you probably have a good master cylinder & rear brakes based on your plugged port to front brakes test. It is possible that the MC moves enough fluid to give a solid pedal with the port to front plugged, but not enough to move the calipers to engage completely, although that seems unlikely.

How are you bleeding the brakes? When you bleed the fronts, is there a good flow of fluid from the bleeders?

Have you looked at the pads & calipers to be sure that the pads are fully in contact with the rotors, not caught a little cockeyed? Nothing springy fallen between pad & rotor or caliper & pads? Calipers slide & are free to center themselves over the rotors?

Tell us about your H-block. What is it from? Some years (78-?? broncos & ?? F150s) have a pin that has to be held out when bleeding or the fronts won't bleed correctly. Some of the earlier fullsize guys have chased their tails for days before finding about the pin. There is also a routine to un-switch the brake warning light switch in an early bronco. Tom's instructions. I wonder if there might be something related to it being off centered. And as mentioned above, reversed lines to the H-block (In & out, or front & rear) could cause issues.

I don't like to do this unless the hoses are about be replaced, but an old mechanics trick is to gently use vise grips to pinch a rubber brake line. They say it is ok if you don't crush the lines, but it still makes me uneasy with brakes. And it seems like it would leave a pinch in those new braided lines. It would show if the problem is beyond or before the hose. So if you have a solid pedal with both front hoses pinched, you would know if the issue is in the calipers. Brakes still spongy would send you looking upstream. Do you still have the old hoses? It might be worth swapping them back in to test if you don't find it otherwise.

If you could post pics of the H-block, calipers, MC, hoses, etc. it might help to figure it out. Sometimes seeing the actual part instead of picturing possibly different parts from memory will help find the problem.

There is good flow to all 4 corners when bleeding. The H block is from a 69 bronco. Ill try and get some good photos

 

[73azbronco]

Lets try a known, with the front port blocked, can you hook the front lines to the rear port which is known to work? If that works, your front lines and brakes are good, your front MC is doinked.