still soft....

[p24-1953]

i have replaced all wheel cylinders (front and rear), front hoses and rebuilt the master cylinder. and i stil have a soft pedal. the first time you push the pedal it goes to within a 1" of the floor. after you have used a few time it is 3" off the floor. i can not get it firmer than that. i even had (paid, professional) someone bleed them for me. no luck still the rear lines are 5 years old and he thinks that is where im letting air in, but if air was coming in through the lines wouldnt the pedal slowly get soft not be soft imediatly after bleeding? the car stops good. it will lock up all 4 tires if you cram on them at 30. so in my wife word am i over anyalizing and not just enjoying

[RobertKB]

i have replaced all wheel cylinders (front and rear), front hoses and rebuilt the master cylinder. and i stil have a soft pedal. the first time you push the pedal it goes to within a 1" of the floor. after you have used a few time it is 3" off the floor. i can not get it firmer than that. i even had (paid, professional) someone bleed them for me. no luck still the rear lines are 5 years old and he thinks that is where im letting air in, but if air was coming in through the lines wouldnt the pedal slowly get soft not be soft imediatly after bleeding? the car stops good. it will lock up all 4 tires if you cram on them at 30. so in my wife word am i over anyalizing and not just enjoying

Sounds like the brakes are not adjusted properly. Also, they tend to be a little bit soft until the new brake shoes are worn a bit. However, you should not have to push the pedal to within an inch of the floor the first time. It should be working after pushing it down an inch. That is why I question the adjustment. I am sure others will have advice also.

[p24-1953]

lou, ... Tim.. Who around here would be able to set these up properly? do yall recommend anyone?

[BobT-47P15]

Did you replace the rear hose in the center? You probably know that the inside of

old hoses can collapse and not let fluid run back, and probably make it a little hard

for it to reach the wheel cyls also. Just a thought.

[Plymouthy Adams]

when the brakes are applied, the pressure is anywhere between 600 to 1200PSI for moderate to hard braking...the system should obviously be showing signs of a leak in order for you to suck air in the system...either they are not fully bled..the master is bypassing or the rubber hoses are soft and ballooning and keeping the wheel cylinders from building pressure

I used Louman's brake guage when I did the 54..I have no clue if any shop in this area has the tool...

[LAKOTA169]

Is your pedal coming all the way up. I was having to pump my brakes to get a solid feel. We put new brakes on and bleed the lines 4 times. Same problem. Paul Curtice noticed my pedal wasn't comming all the way up. We found the the battery cable was getting in the was of the pedal arm. (My battery is under the seat) We moved the cable and now the pedal is firm after 300+miles of around town driving. Maybe check to see if something is touching the pedal somewhere.

[Jim Saraceno]

I agree with RobertKB. pumping the brakes is usually a sign of a needed brake adjustment. Follow the instructions in the download section to adjust the brakes.

Spongy pedal us usually a sign of air in the line.

Edited October 11, 2009 by Jim Saraceno

[Plymouthy Adams]

pumping the brakes is a sign of air in the system, leak..the indication

of brakes needing adjustment is low pedal that stays low reagardless of the pumping..the reason is that the shoes are so far away from the drum surface that all your fluid displacement is used in moving the shoes and no volume left over to apply pressure..as you physically move the shoe..the at rest postion is fixed thus the return springs come to a stop and the fluid remains in the cylinder for the new psiton position due to relocation of the shoe..piston return by the means of the return springs is the force that returns fluid to the master..

[Jim Saraceno]

pumping the brakes is a sign of air in the system, leak..the indication

of brakes needing adjustment is low pedal that stays low reagardless of the pumping..the reason is that the shoes are so far away from the drum surface that all your fluid displacement is used in moving the shoes and no volume left over to apply pressure..as you physically move the shoe..the at rest postion is fixed thus the return springs come to a stop and the fluid remains in the cylinder for the new psiton position due to relocation of the shoe..piston return by the means of the return springs is the force that returns fluid to the master..

Hmmmm... I'll have to disagree with you on this one Tim. Last year when my brake shoe linings for one of the wheels disintegrated (increasing the travel of two shoes to the drum), I made it home by pumping the brakes. I had to give the brakes 3-6 pumps before they slowed the car down making for an interesting ride home, but pumping the brakes did stop the car.

It takes a short while before the springs return the shoes to the original state.

[Plymouthy Adams]

quick pumping of the brake will get your shoes out there if fast enough to prevent the fluid from returning..however..you did not experience a soft pedal..just a firm low pedal..two distinctly different conditions...by what you experience you did lcose the distance by pumping but in hydraulics..you were not able to displace enough fluid..this thread is about low soft pedal that continues to go soft after a few uses...

[Normspeed]

When mine had a low pedal the first time I hit the brakes, then came up after another application, I thought it was air in the lines. But after a few forum members suggested re-adjusting, I tried it and the problem was cured.

[Jim Saraceno]

Okay, now I agree. I guess my problem is the term "soft pedal".

I've always called it a spongy pedal which is an indication of air in the line. In his first post he mentioned that the first stroke went down to 1" from the floor, then later down to 3". I thought he was saying he was pumping the pedal.

[Guest P15-D24]

You still have air in the lines. You most likely have a leak at some fitting or joint. Pressure bleed it. The shoe adjustment sets the final height of the pedal so if it is low after you pump , yes they need adjustment. But your current problem, low pedal that comes up after pumping is air in the line. If it doesn't stop after 2-3 trips around the bleeders with a pressure bleeder you have a leak.

[JIPJOBXX]

Make, steal or borrow a good bleeder or go down to a good brake repair shop and have them rebleed your brakes! I had this same problem for the longest time until I made up one of those bleeder tools someone here showed how to build.

[JIPJOBXX]

One more idea is to clean up your brake bleeder valves and watch closely to see if one of them is leaking. I had this problem also and again as soon as I replaced that little unit all my problems went away! One of mine even broke oft and I had to retape the hole where the bleeder valve goes into the brake cylinder.

[desoto1939]

There are several questions that need to be answered.

1. Do youhave the original Lockeed brakes with the eccentrics.

2. Did you move the eccentric pins

3. HAve you made the minot adjustments on the shoes.

I have the Ammco brake gage that is needed to get the proper arc on the shoes with the inside diameter of your drums.

Contact me if you want to borrow the tool.

Rich Hartung

Desoto1939@aol.com

[p24-1953]

okay, lets see if i can clarify. there was a typo in my original post. the rear lines are 15 years old, so the first thing im going to do is to replace that. the brakes stop good still, and the pedal is firm after the first use each trip. it does not feel "soft" when you use it. when the m/c was going out the brakes had a spongy feel, this is not the same. i guess it should be called a low pedal. i think i have the all the original equipment. when i adjusted the brakes after rebuilding. i spun the tire and tightend the cam bolt on the backside untill the brake engaged then back off 1/4 turn. i did this for each wheel cylinder. I have had local break repair shop look at them and they say they are adjusted properly and they are the ones that bleed them last week.

[Young Ed]

Backing them off 1/4 turn sounds like way too much to me. I tighten them until I can just hear them dragging and leave them.

[Cpt.Fred]

that's what i did, too. just enough so you turn them freely by hand.

after a few miles, i guess i'll repeat that, because i have brand new brakeshoes.

i changed all rubberhoses and installed new wheels cyls, i bleeded them about 3 times and there wasn't any air in there the last 2 times.

still, it appears pretty easy to me to push down the pedal...

did i have too much spinach or are they supposed to be like this?

they do not build up more pressure if i repeat to push, so i thinks there can't be any air left, am i right?

[p24-1953]

kinda sound like we got the same problem.

[Cpt.Fred]

yep:(

[RobertKB]

I still say adjustment in both your cases.

[Normspeed]

I agree. 1/4 turn is a lot to back off. Like Young Ed, I tighten till they lock then back off just until they turn freely. usually more like 1/8 turn.

[RobertKB]

On new shoes, I like just a touch of drag, just a touch.

[Guest P15-D24]

but this symptom " the first time you push the pedal it goes to within a 1" of the floor. after you have used a few time it is 3" off the floor." is air in the lines. If the pedal went down 1-1/2 inches after he used it a couple time he would still have air in the lines, plus the shoes are out of adjustment. But you still have air in the lines maybe caused by a leak. Also the shoes MUST be adjusted with am Ammaco like tool, even it home made, because the shoes have to be centered to the axle. When done right your brakes will come on with around 1 inch of pedal depression and you will be surprised how good they really are. Also take time to review the brake section on the main site.