Sticking front calipers and brakes refuse to bleed

[TylerH860]

The honeymoon is officially over on my 6.9.

Today I had a caliper lock up and catch fire briefly. I let the car sit and cool for 30 minutes, then limped it home so I could yank the caliper. I took the brake to Bob's to find another to swap out, but Bob played with it and said it was working perfectly.

So, I went home, re-attached the caliper, and tried to bleed the brakes. It was just barely a trickle.

Took the car on a 20 minute drive or so, and after 100 stops finally got the confidence to take it up on the highway. Something didn't feel right, so I exited, and this time the right front caliper was smoking.

I can free the caliper again, but they refuse to bleed, and I've introduced air in the system giving some pretty severe fading.

Using the search feature I have come to similar threads where people suggest the rubber brake lines have collapsed causing the calipers to stick and unable to bleed. Sounds like it fits the bill perfectly.

I wish this happened one day earlier, so I could have gotten the parts to do the job over the weekend. Oh well.

Any other suggestions? The only inconsistency to the other threads is it hitting both wheels at different times. Could something further up the brake totem pole be causing this? The lines will certainly get changed anyway, since they look very old, but I curious if there's any other ideas to the cause of the issue.

[Arthur Dalton]

Classic brake hose constriction.

Simple to diagnose:

Jack wheel off ground and press hard on brake pedal...go hand turn wheel..if it is hard to turn , open bleeder ..if it then turns freely.. that hose has an interior restiction and is holding the caliper piston from returning.
If the wheel still is locked after bleeder is opened,,the cal piston is frozen.
Move to next wheel..repeat test

[TylerH860]

Did the test, I happen to have the front wheels off and the car on jackstands currently.

With a pressed brake pedal, the driver's side moves freely. It was not doing this before. Same scenario with brakes depressed.

Passenger side, pressed brakes, locked calipers. Released bleeder, still locked. The brakes won't bleed with the brake pressed, but will trickle out with the brakes not pressed.

Perhaps I'll just do both front calipers, rotors, and lines. The car had been sitting for a while, and it would eliminate everything.

[280EZRider]

Arthur is right, as usual. And I agree with you: do both wheels - rebuild the calipers and replace brake hoses. Rotors only if necessary. The strangest, inexplicable stuff happens to a machine after sitting for a long time, and especially in winter. This past winter, I noticed antifreeze weeping from most likely the water pump. It was too bloody cold in the garage to mess with it, plus the car was avoiding the onslaught of Ohio salty roads - to say nothing of the major pot holes that still exist - so I decided to wait for warmer weather. After it became warmer, the leak had fixed itself!

[Arthur Dalton]

Yes ..sitting is the KILLER of all equipment.

A good thing is to start a stored car once in a while , and move it..even if it is in a garage and you can only move it 2 feet...that 2 feet move will exercise the caliper pistons and MC.
I put them in gear and rapidly pump the brake while creeping forward/reverse..helps the trans too.

Don't forget to open the garage door ...don't want the car to last longer than you....................

[JimmyL]

Originally Posted by Arthur Dalton

...don't want the car to last longer than you....................

It already has.......

[lkchris]

Originally Posted by Arthur Dalton

Yes ..sitting is the KILLER of all equipment.

Being 33 years old contributes!