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Hard brake pedal and hard to stop.

fullmetaljacket

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Hard pedal and the car still is a doozy to stop. Never did this before.
All around 10 inch drum brake car. high 2900 Lbs
All due respects, first and foremost I do not want to change over to factory disc or race.
Can this be something to do with the two hard lines I didn't change coming out of the aluminum master cylinder to the line loc and small junction valve at the chassis?
I changed the rear hard lines on the diff housing, the hard line from the diff to the front junction valve and the hard and rubber lines for the two front brakes, plus the wheel cylinders.
Can this be something to do with the two hard lines I didn't change coming out of the aluminum master cylinder to the line loc and feeding into the small junction valve at the chassis? What gives?
 
So what has changed? Does it have power brakes? Has the master cylinder bore diameter been changed? Wheel Cylinder Diameter? Brake pedal leverage?
 
I have heard of this before - check the flexible rubber lines are not blocked.
Did you fit the correct size wheel cylinders?
 
Hard pedal and the car still is a doozy to stop. Never did this before.
All around 10 inch drum brake car. high 2900 Lbs
All due respects, first and foremost I do not want to change over to factory disc or race.
Can this be something to do with the two hard lines I didn't change coming out of the aluminum master cylinder to the line loc and small junction valve at the chassis?
I changed the rear hard lines on the diff housing, the hard line from the diff to the front junction valve and the hard and rubber lines for the two front brakes, plus the wheel cylinders.
Can this be something to do with the two hard lines I didn't change coming out of the aluminum master cylinder to the line loc and feeding into the small junction valve at the chassis? What gives?
You are not racing and the car and it has a line loc, and the master cylinder is aluminum? Which wheel cylinders did you change and do they have the same bore as your old ones. Also why did you not change the rear rubber line? Usually the rear rubber line is the first to fail. When this happens you will have a very hard petal and front brakes only. This should have been easy to detect when bleeding the system.
 
You are not racing and the car and it has a line loc, and the master cylinder is aluminum? Which wheel cylinders did you change and do they have the same bore as your old ones. Also why did you not change the rear rubber line? Usually the rear rubber line is the first to fail. When this happens you will have a very hard petal and front brakes only. This should have been easy to detect when bleeding the system.
You are not racing and the car and it has a line loc, and the master cylinder is aluminum? Which wheel cylinders did you change and do they have the same bore as your old ones. Also why did you not change the rear rubber line? Usually the rear rubber line is the first to fail. When this happens you will have a very hard petal and front brakes only. This should have been easy to detect when bleeding the system.
I do race it on occasion, but mostly drive it on the street.
It is a manual drum brake '65 car with a aluminum master cylinder. I have replaced the hard line that crosses the differential along with the rear rubber leading up to the front. I have also replaced the front wheel cylinders.
At the front, replaced the hardline that cross over the engine bay along with the rubber hoses that lead into the two front brake wheel cylinders. I've bled the whole system starting with the furthest wheel cylinders on the rear passenger side.
One thing, I didn't know was that there are different wheel cylinder bores. I know that there are different master cylinder bores but never wheel cylinders. I thought that the wheel cylinders were all and the same except for different size mounting bolts between OEM and aftermarket units.
 
do you have the shoes seated properly ? got to ask... I had something of the same in my 55 Dodge.
 
Sounds like the drums and shoes are over heated and glazed.
Drums were resurfaced and new shoes installed as well.
A friend told me I might have the wrong material shoes. These current shoes look like normal shoes to me, but may have some metallic material in it. They were from centric shoes.

As far as shoes seated correctly, I would presume yes, since I have done them for years on the car.
 
Has the car been changed from the single reservoir master cylinder to some kind of dual reservoir unit? 67 was the first year for a dual reservoir system. None of the single reservoir systems were aluminum that I know of. My opinion as all wheel cylinders and rubber hoses have been changed and the system was blead properly is that your problem some how related to the line lock and valve setup along with maybe a defective master cylinder.
 
Has the car been changed from the single reservoir master cylinder to some kind of dual reservoir unit? 67 was the first year for a dual reservoir system. None of the single reservoir systems were aluminum that I know of. My opinion as all wheel cylinders and rubber hoses have been changed and the system was blead properly is that your problem some how related to the line lock and valve setup along with maybe a defective master cylinder.
JH
I'm starting to think that the culprit may be the line loc which I have had on the car since 1990.
Perhaps after sitting for a while, some stuff may have caked up in there, though I would take it around the block here and there and all was fine until recently.
Yes, I got rid of the single iron reservoir back in 1989 when I got the car and installed a dual aluminum unit in its place. Since then, I have installed a new dual aluminum unit about 4 years back with what seemed to be the correct piston size for four wheel drums.

For arguments sake, there were supposedly only a few aluminum single reservoir master cylinders that were produced by the Girling brake corporation for the ultra rare 2% FX cars that Chrysler assembled only four of in 1964.
Either way, I'm gonna change the line-loc and the only two steel lines leading to it from the master cylinder that I did not change. I'll keep y'all informed.
 
While your removing LL I'd look for a 67 or later master and replace yours. Look for master goes what you have power or manual. I converted my 66 Satellite to a dual master, bought 67 power dual master added later front/rear junction. The pictures are from a Mopar Action disc brake swap, note what he said about master bore size. I did the swap and brakes work great.
dd1.JPG
dd2.JPG
dd3.JPG
 
While your removing LL I'd look for a 67 or later master and replace yours. Look for master goes what you have power or manual. I converted my 66 Satellite to a dual master, bought 67 power dual master added later front/rear junction. The pictures are from a Mopar Action disc brake swap, note what he said about master bore size. I did the swap and brakes work great.
View attachment 824211 View attachment 824212 View attachment 824213
I must admit, that after so many years I have never known that car brake shoes need to be bedded with the drums in order for them to work properly. You can call it a Break in of sought. I was just reminded of this from no less then Dr. Diff himself.
Guess I have a date with my car to launch at various speeds and slam on the brakes to get them acquainted with the other parts.
I'll let you guys know as soon as I know.
 
A guy showed me many years ago how to arc the new shoes to fit the drum. To small diameter lay the shoe on its ends and hit the center of the friction material. To large put the bottom of the shoe on the ground and hit the top. You can get the radius of the shoe to fit the drum perfect across its entire surface. I've had pad material that either needs to be bedded or just plain doesn't have god coefficient of friction. Did the diameter of the M/C piston or wheel cylinder diameter change?
Doug
 
As far as I know, the current MC bore is 1-1/32" where as my older MC was 1"
It was suggested that I run that bore size for a four wheel drum setup. Perhaps I need to go to a 1" once again.
As far as wheel cylinders, I didn't know that there are different piston cylinder diameter sizes. Is that correct? Maybe that is the problem.
 
You need to get a 1" MC again. That 1 1/32" MC will give you a higher and much harder pedal. A MC for a manual drum brake 67-69 B Body should be what you need.
 
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