Spongy Mechanical Brakes

I will say that board has a use,it has made quite a bit of money for me.Some seem to think it is the magic fix for brake adjusting.I really can't count the times I've looked at brakes that were installed right,parts fixed right,but then adjusted by the board.Pull right,pull left,soft pedal,hard pedal that won't stop,all by using that gadget.If the brakes are adjusted right,with everything up to snuff the brakes operate fine.The 60/40 is built in already.Just look at the mechanical advantage of the levers.The rear is 20% longer just to start with.If you try to 'adjust in' the 60/40,you are going to have a pedal like stepping on a big coil spring.My favorite was a fellow that spent a couple hundred having his new brake system adjusted up.They pored over the book explaining how to use the board,and when they were done they told him that was as good as mechanical brakes got.The pedal felt like you were stepping on a plum.When he brought it to me he planned on leaving it to be worked on,20 minutes and $25.later he had brakes that would drag all fours.
 
My brakes stop me, but I can't lock them up. You talk about bent rods, are the rear brake rods suppose to have a significant bend ahead of the wheel ?
 
papafickdon said:
My brakes stop me, but I can't lock them up. You talk about bent rods, are the rear brake rods suppose to have a significant bend ahead of the wheel ?
Click to expand...

No, the rods are the same as the fronts. It sounds like your rear brake housings (backing plates) were installed opposite meaning the right side on the left, etc. The levers are rights and lefts with the ends angled inline with straight rods.
 
Thanks for the reply, I had an old timer adjust my brakes several years ago, and I assume he bent them in the process of how he did it. I will check to see if I have end adjustment for new straight rods or if the backing plates were indeed installed incorrectly many many years ago.
 
The old timers I knew (guys who drove Model A's when they were "used cars") always complained about the brakes. I always thought they were just dealing with a worn mechanical system, but maybe they just didn't know how to adjust them! :)
 
Riveted woven linings are inherently a bit spongier than bonded composite. As Keith True said, adding your 60/40 adjustment to the already biased cross shaft ratio will give you a mushy pedal. Been there, threw that adjustment board away a long time ago.
 
Well, my actuating arms are apparently installed opposite because they are offset out instead of in. Do you have to drill out the pins, or can they be driven out in order to switch the arms ?
 
papafickdon said:
Well, my actuating arms are apparently installed opposite because they are offset out instead of in. Do you have to drill out the pins, or can they be driven out in order to switch the arms ?
Click to expand...

I can't imagine attempting to change the levers on the car. If you disassemble everything then you don't need to touch the levers. You simply swap sides and the levers will be correct.
 
I had an old Dodge truck that I couldn't get a good pedal after carful bleeding of the lines and good adjustment of the shoes so I asked the wife to push the pedal while I crawled under to see if I could discern if anything was amiss. I saw the problem alright. The drums were flexing. Someone had them turned way beyond safe.
 
Be patient with my ignorance, but I can not see how switching backing plates would make any difference. The actuating levers are attached to the cam with the offset being to the inside of the car, or away from the backing plate and that stays the same wherever it is. I can't get the image of how switching will position the offset toward the backing plate. I am sorry for being unable to get the picture.
 
papafickdon said:
Be patient with my ignorance, but I can not see how switching backing plates would make any difference. The actuating levers are attached to the cam with the offset being to the inside of the car, or away from the backing plate and that stays the same wherever it is. I can't get the image of how switching will position the offset toward the backing plate. I am sorry for being unable to get the picture.
Click to expand...

When you switch sides you also flip the levers 180*.
 
Last edited:
Are the actuating levers facing up or down? Mine are up with the offset facing away from the backing plate.
 
papafickdon said:
Are the actuating levers facing up or down? Mine are up with the offset facing away from the backing plate.
Click to expand...

That part is correct, but look carefully at the angle of the brake rod pin that would fit the lever. It should hold the brake rod so the front of the rod goes towards the center of the frame as it goes forward.
 
1. When using any type of brake adjusting board device, the board has to remain parallel to the floor board when depressing the pedal to obtain accurate measurements of pedal depression.

2. If the board is at an angle "upwards" from the floor board at pedal contact, proper measurements for each pedal depression measurement will be incrementally "less" than that specified.

3. From the front angular part of the floor board one can double check the 1", 1-1/2", & 2" pedal depressions with three (3) pencil marks on masking tape applied to the side of the pedal arm.

4. The swing of the metal foot pedal is traveling at an arch from the central pedal axis & the tangent to this arch is at approximately a 3-1/2" on 12" angle to the horizontal floor board.
 
Thanks to everyone for the help. If I switch the plates, rotate the levers 180 degrees, does it not matter that my offset is toward the middle of the car instead of the pictures showing it toward the backing plate. Switching the plates without removing the levers will not change how it is pinned to the cam, and as I understand the pictures the lever will still be mounted incorrectly. Why did I get under and look in the first place !!
 
Here is a picture of the drivers side brake rod and lever that has apparently been like this for over 30 years. Driver Side Rear.jpg This is my first attempt to attach a photo, I hope it works.
 
That's the kind of bend I figured you had in mind. It's someone's attempt at shortening the brake rods. Just remove the rod and straighten it, and fix the real problem, which might be drums turned too much, or worn brake shoes.

From what I can see the lever looks OK, so you may not have to switch sides. Just look at the brake eye and see that it fits nicely into the slot, which is angled to let the brake rod slant inwards to meet the brake crosshaft.
 
I looked a a couple of backing plates I have and in Brattons's catalog and the offset is in toward the backing plate not out as yours is. The lever also has a slight twist in it so the brake rod points in toward the center of the car to line up with the brake cross shaft.

Bob
 
You must log in or register to reply here.
Back
Top