mechanical vs. hydraulic brake systems

I have changed from hydraulic brakes back to original mechanical brakes for a fellow club member. I did the job correctly and restored all wear in the total system with the addition of cast iron drums and original type soft linings. The owner was tired of replacing leaking wheel cylinders every few years. He is now very happy with the way his Model A stops.
 
Having twice sold complete Model A mechanic brake assemblies (including 19" wheels) to purists for pennies on the dollar, I don't quite understand why the complaining about the cost of switching from hydraulic back to mechanical brakes. I have two A's with hydraulics installed 20 years ago and have yet to have a leaky wheel cylinder. Perhaps it's because I drive them all of the time.
 
Most people don't use their model A for primary transportation. Because of insurance and some tag restrictions most model A's are only fun drivers. Mechanical brakes are more practical for the average model A. Mechanical brakes are a big reason why so many model A's have survived for so long. The average guy doesn't know much about either type brakes and figures that because modern cars use hydraulic that hydraulic must be better, There is really a lot more to it. Hydraulic brakes don't necessarily need less pressure to depress the brake pedal. Early hydraulic brakes needed more pedal pressure than modern versions . It all depends on the size of the wheel cylinders, master cylinder and whether they have vacume assist. A person that can't figure out how mechanical brakes work would have a much harder time with hydraulics when problems occured .
 
Drums are mechanical, as are disk brakes --that which is putting force on the wheel and all they way to the ground via the tire to stop the car... It seems only hybrid cars have some non-mechanical breaking --electrical regenerative braking in addition to their own disk brakes.
 
The difference is activaction .. Mechanical brakes are mechanically activated through levers and rods. Hydraulic brakes are activated by licquid-fluid pushed by pistons ,forced through tubing and hoses to more pistons that activate the shoes or pads. If fluids leak activation is lost and brakes fail. There must be no air in the system or the activation hesitates or the pedal must be pumped. Bleeding air from the brakes is a pain and a process that the average person won't be able to do unless they are experienced . Pistons stick in wheel cylinders if not in regular use. Rubber parts in wheel cylinders and master cylinders are not durable like rods and levers in mechanical brakes. When rubber parts fail, fluid leaks. When one wheel cylinder fails, you might as well replace them all because they will soon follow suit . Metal tubing can rust and leak or just leak and lose fluid and brakes fail . Rubber brake hoses will sooner or later collapse inside and lock up the brakes on the wheel that they connect to.

Hydraulic activated brakes are better suited to modern cars because tubing and licquid activation is easier to route than mechanical lincages because of modern car design . Hydraulic activation has no other advantage over mechanical activation and many disadvantages on the model A as described in the previous paragraph .

The model A is a simple design built for the common man at a simplier time. Mechanical activation is more durable and can sit for many years and still work the same as the last time that they were used . With mechanical brakes there is no fluid to leak, no tubing or rubber parts to fail. This is all a big reason that model A's have survived for such a long time .
 
Purdy Swoft said:
The difference is activaction .. Mechanical brakes are mechanically activated through levers and rods. Hydraulic brakes are activated by licquid-fluid pushed by pistons ,forced through tubing and hoses to more pistons that activate the shoes or pads. If fluids leak activation is lost and brakes fail. There must be no air in the system or the activation hesitates or the pedal must be pumped. Bleeding air from the brakes is a pain and a process that the average person won't be able to do unless they are experienced . Pistons stick in wheel cylinders if not in regular use. Rubber parts in wheel cylinders and master cylinders are not durable like rods and levers in mechanical brakes. When rubber parts fail, fluid leaks. When one wheel cylinder fails, you might as well replace them all because they will soon follow suit . Metal tubing can rust and leak or just leak and lose fluid and brakes fail . Rubber brake hoses will sooner or later collapse inside and lock up the brakes on the wheel that they connect to.

Hydraulic activated brakes are better suited to modern cars because tubing and licquid activation is easier to route than mechanical lincages because of modern car design . Hydraulic activation has no other advantage over mechanical activation and many disadvantages on the model A as described in the previous paragraph .

The model A is a simple design built for the common man at a simplier time. Mechanical activation is more durable and can sit for many years and still work the same as the last time that they were used . With mechanical brakes there is no fluid to leak, no tubing or rubber parts to fail. This is all a big reason that model A's have survived for such a long time .
Click to expand...

And with hard rubber tires you never had to worry about a flat tire.
Bill
 
Ericr,
A conversion to hydraulic brakes in a Model A could require more pedal force or less pedal force depending on how the hydraulic cylinders are sized. Generally, if you convert to a later model Ford hydraulic brake system, that system will require less pedal force to slow or stop a Model A.

The Model A's mechanical brakes do not require extraordinary pedal force if the brakes are in good working order. Unfortunately, many Model A's have mechanical brakes in poor condition giving the mechanical system a bad and undeserved reputation.

It's ironic how we tend to easily spend money on bling items and skimp on the parts that can kill you!
 
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