Brake adjustment

Tom Endy

Tom Endy

Well-known member
What is the consensus in the Model A kingdom about the manner of a brake adjustment for new brakes with the soft composite linings?

Should all four wheels come in at the same time?

Should the back wheels come in ahead of the front wheels?

Should the front wheels come in ahead of the back wheels?

Tom Endy
 
My understanding is that when 'new', the Model A was designed to activate the rear brakes first. The world in that era had more dirt roads than paved, so 'dragging ' the rear end while steering the front made sense.
All opposite today with hard paved roads.
 
I have all 4 come in at about the same time.

I'm a brake board guy. That board can be used to set the brakes any way you like.

I don't think our little light cars have the weight transfer like a larger heavier car so I don't set the front brakes for operation as in a newer heavier car.

I can lock all 4 equally at 35-40 mph. Seems like thats about about as good as it gets.
 
Tom,
By design the model A brake levers on the rear are longer and the rears are (were) suppose to activate sooner than the fronts. You can tell that when doing a proper 4 wheel brake adjustment with all wheels off the ground . If the front wheels would lock at the exact same time you wouldn’t have adequate steering ability. All that said there is a fine line of adjustment. It’s absolutely important you have great brakes out back but the fronts need to do their job well. Drive a Model T and you’ll know…

I like the molded linings, but there are good and bad with that as well. I think overall the molded linings ( bonded or rivited) are the way to go with the cast iron drums. We are blessed to have 3 great suppliers, Randy’s being the most economical of them and a proven product in my opinion. There will be some who disagree but then I would ask show me any evidence.

I like a harder pull as much as possible on the fronts as much as possible on adjustment on a new brake job. I break them in quick and tweak as needed. They can all screech to a stop when done.
Ensuring all is good on restoring all brake components and proceeding with proper adjustment of each wedge first rods are adjusted to remove all play and pulled for equal wheel tension when brakes are applied at the lock up Point.
Adjust as needed.
Test drive, break them in and adjust as needed.
Larry
 
This discussion got me thinking about the design of the brake system.

Since the rear brake levers are longer than the front, it would seem that the rear brakes would activate later than the front ones, since the rear brake lever would have to be pulled further to achieve the same distance of travel as the front brake levers. And, the brake rod arms on the cross shaft all seem to be the same length, although I haven’t actually measured them.

The difference must be in the design of the rear brake cams vs the those on the front. Again, I haven’t measured the difference in front vs rear cams.

I would love to hear further comments/discussion about this.

Thanks - Jim
 
I use the board also, and all 4 come in about the same time, and I agree with Larry about
Randy Gross's expertise. He did my brakes and steering box. Cant say enough good things about his work.
 
Because the rear linkage lever is longer than the one for the front, the rear brake is applied with more force at the same brakepedal pressure.
 
Front brakes should never engage first. The back end can come around and loose control of the car. The purpose of the back brakes engaging ahead of the front is to keep the car braking in a straight line.
 
Tom, I think all four brakes should com on at the same time. The 11" drums all around were as good as they understood at the time. However, todays larger discs and callipers in front show that at least 60% to 75% of braking is provided by the front brakes and all brakes all come on at the same time. Some will argue we don't have disc brakes but we do have the same physics today as back then. We are considering stoping a mass in a straight line and weight is travsferred forward.
I also realize attention to detail in rebuilding brakes is most important.
Al
 
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