Brakes Front brakes heating up, pressurizing fluid, pedal stays up

MRaburn

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Nov 29, 1999
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@Mustang5L5, I was told you were the guy to ask. :p

Trying to finish up my 86 project. Having brake issues.

I replaced front suspension, bearings, rotors, calipers, lines, and master cylinder. Didnt touch the rear drums.

When driving, the front rotors are heating up to the point where if I put a hose to them they would steam. Under no braking, as in driving down a highway, when it comes time to stop, the pedal is solid, as in I cant push it down at all, as though the fluid heated up, expanded and the breaks are already at full expansion, and when I try to stop, I have to push real hard on the pedal as though I was driving with manual brakes and the pedal will only move about 1". It takes a bit to stop.

I have to assume the calipers are not opening back up and the pads are riding on the rotor and generating heat.

Any ideas? The calipers are just simple repops from LMR and the rotors are from Stoptech. I would like to find some upgraded calipers like Wilwood, but want to keep the stock spindle and 4 lug.

Thanks guys! My resto project is almost done!

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PS. No the Bronco in the background is not for sale :)
 
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Mustang5L5

i'm familiar with penetration
Mod Dude
Feb 18, 2001
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First thing would pop into mind would be booster pushrod adjustment. If it is protruding too far, it causes the front brakes to drag and not fully release.

it could be the calipers themselves, but unlikely both would be stuck at the same time. That usually points to a common issue like MC or booster rod.

with the front wheels off the ground, do they turn freely?
 

MRaburn

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Nov 29, 1999
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Mike,

I've got to go on vacation this week, so when I get back it is going on the lift. I will keep you posted with what a find.

FYI, before I replaced all the brakes, when I first started driving it again after it had sat up for several years, the front brakes were completely locking up and dragging the front wheels on my gravel driveway. So I told myself maybe the calipers were stuck and replaced them along with the rotors, bearings. Before that I had replaced the master cylinder because I had NO brakes, pedal to the floor. Now the pedal is at the top and still heating them up, although they are not locking up (yet).

I was thinking I could replace the booster and the master cylinder again. Any thoughts on the proportioning valve?

I'll post an update in a week when I get the wheels off on the lift.

Thanks
Mike
 

Mustang5L5

i'm familiar with penetration
Mod Dude
Feb 18, 2001
34,010
10,289
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Massachusetts
I have seen a PV rust up inside, but the brake system on the car was nasty. Prob never changed since the 80s and full of fluid. Upon opening the combo vskve, it was a rusty mess. There were signs as to what I was going to find however. For the most part, most of the ones I’ve dissected have been ckean. So if you suspect there may be internal corrosion, you can certainly pop the front plug off and take a look. Should be pretty obvious if it’s corroded in there.
 

7991LXnSHO

Now I want a 10 year badge
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Sep 1, 2010
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Tell us if Goofy wears a mask
Inquiring minds want to know.
Since your brake questions are hopefully answered, here are questions for the trip.
If Goofy and the mice are wearing full head masks, does that count? Do Sleeping Beauty or Snow White have to wear masks while cursed and sleeping? And has Prince Charming been tested?
 
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