Disc and Drum Brake Restoration
All hydraulic brake systems are prone to failure, simply from age and mileage. Even if they feel right, brake parts should be inspected periodically. Check for leaking fluid from calipers and wheel cylinders. Also check old brake fluid for high moisture content, swollen brake hoses, and rusted brake lines.
Steel Brake Lines and Rubber Hoses
The flexible rubber brake hoses under your old car dry out and crack, causing a leak or a soft brake pedal. Bend each line and check to see if you see any cracking in the rubber that opens up. If in doubt, replace them.
Check all of the metal brake lines under the car and make sure there isn't any major corrosion or rust on the lines.
Read: How To Make Brake Lines
Rebuild or Replace Wheel Cylinders
Through years of sitting, the wheel cylinders in an old car will start to leak. Although it is usually faster to replace one than rebuild one, there are several reasons for rebuilding a wheel cylinder. The first is the quality of replacement units.
Most of the new wheel cylinders you see advertised are made overseas, and they were designed to be manufactured as cheaply as possible. If your original cylinders are safely rebuildable, this is always a better choice. Rebuilding wheel cylinders is generally cheaper than replacing them, but it does takes longer.
Read: Rebuild Wheel Cylinders
If you inspect your brakes regularly, a leaking wheel cylinder may be caught before any damage is done. If more than a few drops of brake fluid get onto your brake shoes, the shoes should be replaced.
Sometimes you'll need to repair or replace a wheel cylinder because of a broken bleeder screw. It may have sheared off while trying to loosen, or be so old and deteriorated that opening it isn't possible. This makes replacement a better option.
Drum brakes may not be high-tech, but that's what stopped most cars from the thirties to the sixties. If you have never changed brake shoes before, a good idea is to do one side at a time. This way if you get lost, you can use the other size for reference.
Read: Drum Brake Tools
Read: Overhauling Drum Brake Systems
If your classic car is mostly for show, the stock drum brakes will suffice. But upgrading to disc brakes makes your old car safer and more driveable, and if you're adding horsepower, it becomes a necessity. One of the most popular classic car upgrades is front drum to front disc brake conversion.
Disc Brake Conversion For GM A-Body Cars
There are several ways to convert from manual drum front brakes to power discs for GM A-body cars, which include the 1964-1972 Buick Skylark, Olds Cutlass and 4-4-2, Pontiac Lemans and GTO, and Chevy Chevelle and Monte Carlo. Over the years, I've owned several A-body cars, including my old 1970 Chevelle. It was common back in the day to convert from drum to disc by using parts from another A-body car.
Read: Convert Front Drum Brakes To Disc Brakes
Similar to engine oil being changed, brake fluid needs to be changed periodically, or it could contaminate other brake parts. A quick look in the owner's manual shows manufacturers' recommended maintenance of replacing brake fluid at is at least every three years.
Read: Best Brake Fluid For Classic Cars
Read: Painting Brake Calipers