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OK, the link below is the front disc brake setup that my 63 Gals previous owner had installed. The rears are still the stock drums. Vacuum to the system is supplied by a Leeds vacuum pump. Normal braking is just fine.

https://www.autocityclassic.com/fullsize-ford-brakes/1957-1964-ford-fullsize-front-disc-brake-conversion/

When the car is cold sitting in my shop I can roll it by hand myself. When I first start to drive the car cold everything feels normal with no rolling resistance. But as the car warms up and I make a few stops a rolling resistance starts to develop. If I pull up to a red light on a slight hill that normally you would start to roll back on if you released the brake, I can feel the car locked in place and it wont roll back. You can feel that in all aspects of driving weather forward or backwards. I have backed off the rear brakes as much as safely possible thinking that may help, but still the same. And I don't smell that heavy burning brake smell either. Trying to back into a parking spot at the donut shop cruise morning Saturday the car didn't want to roll back in.

I am thinking about replacing the master cylinder and the proportioning valve. Otherwise I am at a loss to figure this out. Any help would be appreciated.
 

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I'd start by determining which wheel(s) are causing the problem. Try feeling the center of the wheels carefully, they will likely be hot. :) That should at least help you narrow it down. That said, my guess would be the front calipers aren't releasing fully. What is the condition of the rubber brake lines? These can deteriorate and fail internally. When that happens, they act as somewhat of a one-way valve. You can overcome the resistance with your foot but when you release the pedal, the hoses prevent the brakes from fully releasing.


Pat
 

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OK, the link below is the front disc brake setup that my 63 Gals previous owner had installed. The rears are still the stock drums. Vacuum to the system is supplied by a Leeds vacuum pump. Normal braking is just fine.

https://www.autocityclassic.com/fullsize-ford-brakes/1957-1964-ford-fullsize-front-disc-brake-conversion/

When the car is cold sitting in my shop I can roll it by hand myself. When I first start to drive the car cold everything feels normal with no rolling resistance. But as the car warms up and I make a few stops a rolling resistance starts to develop. If I pull up to a red light on a slight hill that normally you would start to roll back on if you released the brake, I can feel the car locked in place and it wont roll back. You can feel that in all aspects of driving weather forward or backwards. I have backed off the rear brakes as much as safely possible thinking that may help, but still the same. And I don't smell that heavy burning brake smell either. Trying to back into a parking spot at the donut shop cruise morning Saturday the car didn't want to roll back in.

I am thinking about replacing the master cylinder and the proportioning valve. Otherwise I am at a loss to figure this out. Any help would be appreciated.
you need adjust brake booster pushrod...

its not fully releasing master cylinder...
as you use brakes , they heat up and fluid expands and has no where to go..
therefore your brakes start dragging...


i was dealing with the same issue.. i also had to add a return spring on pedal
as the weight of pedal it self was activating pressure valve in booster slightly..(i know it sounds crazy..but true..)


watch this video first, before going out and buying bunch of new parts....start about 5 min in..




 

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Both of the above suggestions have led to conditions as the OP has described in my experience. The weak hoses tend to only affect one wheel and can usually be determined by the heat being generated by the dragging brake. The excessive length pushrod will display itself thru all 4 wheels displaying excessive heat.


The hose issue happens when the interior of the hose deteriorates to the point where a flap of rubber may flip back preventing the brake from releasing much like a check valve would do. The easy way to demonstrate this is that after you've determined which wheel is not turning, raise the tire off the ground and crack the line at the caliper or drum. If there is a spray of pressurized fluid that now allows the wheel to turn you've verified the problem.


Disclaimer: Use all necessary safety precautions when working on a car lifted off the ground.
 

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I'd start by putting the car on 4 Jack stands, then pushing the brake pedal several(think the usual.number of time before you feel the drag driving) and try to turn each wheel by hand. If all 4 wheels lock, this may be the master cylinder, or pushrod length. If only on locks, this could be line issue, caliper sticking, or caliper slides sticking. If its front or back brakes dragging, could still be master cylinder, or booster pushrod length, or maybe even the pedal not fully releasing causing the front, or rear, to stay partially engaged.

It's best to do a little more investigative work before just spending money on parts.


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He can check his pedal pushrod length simply pulling back on the pedal and carefully let it reseat in the back of the booster piston, there should be a brief dead space before the metal engages the booster. No need to jack up, pump, etc. It's not as big of a deal as we're making it out to be.
 

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I'm glad to hear that I'm not the only one with the braking issue you describe. The previous owner of my 63.5 427 car had installed Master Power Brakes power 4 wheel discs on my car. They seemed fine on the limited test drive I did before I bought the car. Shortly after I bought it I took the car apart for a major restomod treatment. From the time we got it back together, it has had this issue. We have done and tried everything mentioned so far, and then some, talked to numerous experts . . . can't solve it (yet!). It's definitely booster pushrod related. I have become comfortable driving the car the way it is, and when the car starts slowing itself down (feels like regenerative brakes on electric cars) I just hook a foot under the brake pedal, pull it up a couple of inches, and we're back to fine for a while. When the brakes start to drag again, repeat previous steps. As an aside, if you are using the OE hydraulic brake light switch, your brake lights will come on and stay on at the same the dragging is taking place until the hydraulic pressure bleeds off. So when you come out of McDonald's and see your brake lights are on and go "WTF", that's why. RAGGAREN, do you have a description and picture of the brake pedal return spring you installed in your car? I have thought about installing one but I haven't figured a way to do it that would look good so I would be interested to know what you did. Thanks. And for the rest of you, when you find a solution to this please let us know. Thanks!
 

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He can check his pedal pushrod length simply pulling back on the pedal and carefully let it reseat in the back of the booster piston, there should be a brief dead space before the medal engages the booster. No need to jack up, pump, etc. It's not as big of a deal as we're making it out to be.
Yeah totally not needed to ACTUALLY figure out what's going on. I totally steal money from customers everytime I go through these steps as a PROFESSIONAL.

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Discussion Starter #9
I'm glad to hear that I'm not the only one with the braking issue you describe. The previous owner of my 63.5 427 car had installed Master Power Brakes power 4 wheel discs on my car. They seemed fine on the limited test drive I did before I bought the car. Shortly after I bought it I took the car apart for a major restomod treatment. From the time we got it back together, it has had this issue. We have done and tried everything mentioned so far, and then some, talked to numerous experts . . . can't solve it (yet!). It's definitely booster pushrod related. I have become comfortable driving the car the way it is, and when the car starts slowing itself down (feels like regenerative brakes on electric cars) I just hook a foot under the brake pedal, pull it up a couple of inches, and we're back to fine for a while. When the brakes start to drag again, repeat previous steps. As an aside, if you are using the OE hydraulic brake light switch, your brake lights will come on and stay on at the same the dragging is taking place until the hydraulic pressure bleeds off. So when you come out of McDonald's and see your brake lights are on and go "WTF", that's why. RAGGAREN, do you have a description and picture of the brake pedal return spring you installed in your car? I have thought about installing one but I haven't figured a way to do it that would look good so I would be interested to know what you did. Thanks. And for the rest of you, when you find a solution to this please let us know. Thanks!
Thank you 635. I guess its comforting to know I'm not alone. Now that I know what the problem likely is, I tend to key in on the not so obvious also. By not so obvious I mean things like I have noticed how really close a couple of my steel brake lines are to my shorty headers. They have to pick up a ton of heat. I am also thinking to upgrade to dot 4 (5 not being compatible with 3 or 4}. I have just added a spring to my brake pedal as Reggaren did. This job as yours did, will grow bigger in scope so I have decided it is above my pay grade. Its going to my fantastic mechanic Friday. He has my OK to replace anything. But also to think outside the box. I have my Gal right where I want her now except for this brake issue so I will be very aggressive on this. My ride last Saturday was not enjoyable with these brakes. If needed I will replace everything. ----- I talked to Auto City Classics this morning and they told me my disc brake conversion was based on 1978 Corvette master cylinder.
 

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Yeah totally not needed to ACTUALLY figure out what's going on. I totally steal money from customers everytime I go through these steps as a PROFESSIONAL.

Sent from my SM-J727V using Tapatalk

Ooh, yeah I should have gleaned your greatness from the positive vibes emanating from your post. Sure hope you at least ACT as PROFESSIONAL as you come across on this forum.


*******!
 

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RAGGAREN, do you have a description and picture of the brake pedal return spring you installed in your car? I have thought about installing one but I haven't figured a way to do it that would look good so I would be interested to know what you did. Thanks. And for the rest of you, when you find a solution to this please let us know. Thanks!
i had a extra pedal assembly for my 57 chevy..
i scavenge the spring from that...
i was a sob to install on the galaxie pedal ...
but works great.....





 

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I'd start by putting the car on 4 Jack stands, then pushing the brake pedal several(think the usual.number of time before you feel the drag driving) and try to turn each wheel by hand. If all 4 wheels lock, this may be the master cylinder, or pushrod length. If only on locks, this could be line issue, caliper sticking, or caliper slides sticking. If its front or back brakes dragging, could still be master cylinder, or booster pushrod length, or maybe even the pedal not fully releasing causing the front, or rear, to stay partially engaged.

It's best to do a little more investigative work before just spending money on parts.
that is real hard to replicate if you are not actually driving the car...


brake fluid get heated up from the friction by rotors and drums and then slowly expanding more and more,
the hotter brake components gets..
 

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Thank you 635. I guess its comforting to know I'm not alone. Now that I know what the problem likely is, I tend to key in on the not so obvious also. By not so obvious I mean things like I have noticed how really close a couple of my steel brake lines are to my shorty headers. They have to pick up a ton of heat. I am also thinking to upgrade to dot 4 (5 not being compatible with 3 or 4}. I have just added a spring to my brake pedal as Reggaren did. This job as yours did, will grow bigger in scope so I have decided it is above my pay grade. Its going to my fantastic mechanic Friday. He has my OK to replace anything. But also to think outside the box. I have my Gal right where I want her now except for this brake issue so I will be very aggressive on this. My ride last Saturday was not enjoyable with these brakes. If needed I will replace everything. ----- I talked to Auto City Classics this morning and they told me my disc brake conversion was based on 1978 Corvette master cylinder.
heres also another way of testing if you have a pushrod issue..
loosen the two nuts holding master to booster slip 1or 2 washer on to
threaded stud between master and booster, then tighten back down..
go for a test drive...
if working normal, then you know pushrod is adjusted out to far...
 

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Discussion Starter #14 (Edited)
i had a extra pedal assembly for my 57 chevy..
i scavenge the spring from that...
i was a sob to install on the galaxie pedal ...
but works great.....





Raggaren did it the right way. In order to get it done quickly for now, I just got 2 medium hard about 5 inch springs from hardware store and 2 medium S hooks. Hooked the 2 springs together end to end. And via S hook one spring end went high up on brake pedal bar{I had good spot where it wont slip down) and the other end to a spot under dash on left side of steering column. Kind of mickey but very functional and out of sight til I get this brake issue figured out. ------ Also I am looking at how close my brake line steel tubes are running close to my headers. I know it does not cause the problem but I believe heating the lines up so much certainly does no good.
 

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that is real hard to replicate if you are not actually driving the car...


brake fluid get heated up from the friction by rotors and drums and then slowly expanding more and more,
the hotter brake components gets..
The brake fluid will not, or at least should not heat up on it's own. There is an initial locking, sticking, dragging condition that has to generate heat in the components. Even if it's something like the booster bad internally causing it to hold pressure when it shouldn't ( I have seen it happen on another aftermarket disk brake conversion) and dragging the brakes.

Maybe the lines being too close to the headers is causing it, if that were true, running it for a little bit on stands would yield some results. In over 20 years of automotive experience, more than a decade professionally, through all the manufacturers trainings I have been certified in, including brakes, no one ever told me that there is always "xyz" fix for "abc" problem. I'm not saying I know everything, or that I've seen everything, because I dont and I haven't. All I'm saying is having all the information possible, and doing as much diagnosis as possible, will yield the best results 99% of the time.

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The brake fluid will not, or at least should not heat up on it's own. There is an initial locking, sticking, dragging condition that has to generate heat in the components. Even if it's something like the booster bad internally causing it to hold pressure when it shouldn't ( I have seen it happen on another aftermarket disk brake conversion) and dragging the brakes.

Maybe the lines being too close to the headers is causing it, if that were true, running it for a little bit on stands would yield some results. In over 20 years of automotive experience, more than a decade professionally, through all the manufacturers trainings I have been certified in, including brakes, no one ever told me that there is always "xyz" fix for "abc" problem. I'm not saying I know everything, or that I've seen everything, because I dont and I haven't. All I'm saying is having all the information possible, and doing as much diagnosis as possible, will yield the best results 99% of the time.

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correct.. brake fluid will not heat up on its own...
but driving in traffic or short stop and go conditions for example..
calipers start to warm up.. as warming up ,fluid starts to expand some..
thats normal and excess flows back into bowl when releasing brake..


just getting buy headers alone will not cause dragging brakes, since expanding fluids can still flow back into bowl..and pistons retract..
blocked lines..deteriorating old lines etc..miss adjusted booster rod and so on...causing blockage etc..
with fluids having no where to go.. the more the brakes drag the hotter fluid in caliper get and expand..the tighter the brakes apply/drag....


being a disc brake conversion , a lot is pointing to booster and master cylinder... miss adjustment/miss match..
some troubleshooting and fixes should get him back on the road again..:wink2:
 

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I ran into a similar issue when I converted my '64's brakes a few yrs back --needed just a smidge less pushrod length, so I removed the brake pedal's return bumper, rigged up an adjustable one to try and get that last bit of length, and with that now there......I was able to come off of the stud part of my new bumper with a small bracket to then mount a universal type electric b/l switch further back on the brake pedal. To keep the switch's button firmly 'off' when the brakes weren't being applied, I then added a long but light return spring.

All of that has been down there for a few seasons now --but Lars I do love your spring idea !! :tup:

IMG_20190801_204202272 by 1964 Galaxie 500, on Flickr

i had a extra pedal assembly for my 57 chevy..
i scavenge the spring from that...
i was a sob to install on the galaxie pedal ...
but works great.....
 

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Discussion Starter #18
Update ------ Saturday morning arriving at my great mechanic David's lift bay, as I pulled in, my car did not want to roll. We immediately loosened the master cylinder from the power booster and as soon as we pulled the master cylinder away the pressure was relieved at the brakes and the car could roll by hand. We looked at the adjustment on the PB rod and it was shortened already to the max. As we tried to mate the two units back together you could feel a resistance at roughly 1/8 inch from flush fitment. So we started by putting a thick washer on both studs and retightened the MC onto the booster. Test drove, had a touch more brake pedal travel, braking was good, and the brake seemed to bind less but did still bind. We then put a second washer on and test drove. During third test drive I braked hard numerous times, caught signals, and drove quite a ways and thought the issue was solved until I pulled back into the bay and felt a very slight drag. But this time we let the car sit a bit and it then rolled freely.

Decided for now to leave the spacing were it was (.20 inch) and look at some other issues. As I've said my brake lines ran really close to my 406's shorty headers. Took the cap off master cylinder and the fluid smelled burnt. Thinking it may be Dot 3 we drained it all and refilled the whole system with new Dot 4. During this process we slipped high temp brake/fuel line sleeves on brake line areas closest to headers. While up on the lift the brakes were checked and all looked good.

So I left David's shop wanting to put some miles on it. Took my daughter and granddaughter on a ride. Everything seemed just fine, no dragging at stops. Pulled into my home shop and it felt just slightly dragging again?????? Waited a bit and I could push it freely. So its really close now. If I had a paper thin washer to add I would have tried it. As soon as I'm sure its all right on, my best friend (machinist rod owner} will make a custom full spacer to replace the washers.
 

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right on Willy...
noting like the smell of success....:tup::grin2:
 

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Discussion Starter #20
right on Willy...
noting like the smell of success....:tup::grin2:
Raggaren ---- Thanks to all the help from you and the others here I was able to get it dialed in real close. That video you posted was great. If I can find a paper thin washer I may add it. Below is a picture where you can see the two spacing washers.
 

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