Whether you’re just maintaining your “driver” or completely restoring a vehicle, you’re going to want to give the proper attention to the brake system for obvious reasons. Hydraulic brake systems will deteriorate over time, particularly if the vehicle has been sitting. All those soft seals that keep the fluid from leaking will dry out and loose their flexibility if they’re not used. The presence of moisture can also lead to corrosion of the system’s metal parts. Brake fluid is naturally hydroscopic (meaning it wants to absorb moisture). Moisture will promote rust in the system which can cause wheel cylinders and disc brake calipers to bind or seize causing poor or no braking. Rubber brake hoses can also maintain proper outward appearances while becoming soft from the inside out. Rust will also plague steel brake lines on the chassis from the outside and can ruin friction surfaces of brake drums and rotors. In general, long-term dormancy, even when your car is stored indoors, can be hard on brake systems.
For those of you not familiar with how your brake system works, here is a simple step by step explanation of how brakes work. When you step on the brake pedal you are exerting mechanical pressure on a hydraulic cylinder. This is the master cylinder which now sends hydraulic pressure to each of the four wheels. The pressure is transferred through steel and rubber brake lines to each brake assembly. The hydraulic pressure in each of the wheel cylinders (or calipers if you have disc brakes) is then converted back into mechanical pressure to move the brake pads or shoes to make contact with the brake rotor or drum. Wheel cylinders on a drum brake assembly push out the brake shoes within the drum to make contact with the inner machined surface of the drum. Calipers will squeeze the brake rotor from each side to slow it down and stop your car.
The primary advantage of disc brakes over drum brakes is that they dissipate heat quicker than drum brakes do. They also shed water quicker as opposed to a drum assembly that could hold water after a deep puddle and cause poor or no braking for a few scary moments. Brake pulling is also minimized.
When doing the brakes on your classic you will have to decide if you want to keep the brakes exactly as they were when your car left the factory or do some upgrades to make them and your car safer. Up until the early/mid 1960’s most cars had a single master cylinder. This was a single reservoir that supplied pressure to all four wheels. The draw back to this design is that if you lost pressure in any one part of the system you would essentially loose all braking power. In the mid 1960’s, manufacturers started using a dual master cylinder. This separated the front hydraulics from the rear so that if you lost either one due to a bad line, hose or cylinder you still had the other. This was a very important safety advancement that all of today’s cars still use and you should consider for your classic. It takes away a small portion of originality but I believe the safety gained is well worth it. The original single master cylinder could always be re-installed down the road if a purist buys the car from you.
The other most common upgrade is to convert your front brake drum system to disc brakes. This is more involved and expensive than the previous upgrade I explained. If you are doing a basic restoration this may not really be needed for your car. If you have upgraded other things on your car such as the engines horsepower, suspension or other systems and originality is not critical to you then a disc brake conversion would be a suggested improvement. There are kits available these days that keep the installation labor to a minimum and are less expensive than you might think. In some cases you might be surprised how for only a relatively few more bucks you can convert to disc as opposed to a complete drum brake rebuild.
Adding a power brake booster is another way to upgrade your brakes. Most cars can be easily converted to a power system with this installation. It drastically reduces the amount of pedal effort required to get your car stopped quickly. Many customers have had this conversion done to make it easier for their wives to safely drive the car.
As far as the steel brake lines, many companies now offer pre-bent lines ready to go in either regular steel or stainless steel. If these are not available for your application, new lines can be made up from pre made lengths of brake line or cut to fit from a roll of tubing and bent to fit as needed. When making up the steel lines that run along the chassis, we use either copper/nickel alloy or coated lines that will prevent any rust from the outside elements.