Drum Brake Restoration

Many restorers can only dream of taking their vehicle off the road to do a total ground-up restoration. For most it's too large a commitment of money, time and, quite frankly, the garage space to do it. A good alternative is to restore while you drive. The advantages are obvious—your favorite vehicle isn't off the road for years at a time and the drain on the family budget is more gradual. The key to being successful with the restore-as-you-drive-approach is to concentrate on one area of the vehicle at a time, prioritize the mechanical aspects to make it a safe and dependable driver first, then concentrate on the cosmetics later. Our '69 Buick GS 400 is a perfect example. It badly needed new universal joints so we removed the driveshaft, fully cleaned and painted it, installed new U-joints and put it back in the car. A couple of paychecks later we removed the trailing arms, cleaned and painted them, installed new bushings and hung them on a totally "ugly" rear end housing. In this installment we will clean, detail and rebuild the rear drum brakes, which leaves only the axle tubes and differential housing to clean and paint. By then, the entire rear end and driveshaft assembly will be restored and the car will have been off the road only one day at a time.

Prep
Restoring drum brakes (front or rear) is quite simple and inexpensive. Because most collector vehicles since 1965 feature front discs and rear drums, we will cover restoring rear brakes. To get started you need to jack up and support the rear of the vehicle with jack stands and remove the wheels and tires. Make sure that the emergency brake is off so that you can remove the brake drums. Our Buick had a little surface rust around the axle flanges and where the wheel studs fit through the drums so it took a few light taps with a dead-blow (soft plastic) hammer to get the drum off. If it's really stubborn, remove the rubber adjuster plug and back off the brake show adjuster to take pressure off of the drum.


With the drum removed, a quick visual inspection will tell you how involved this resto segment will be. The brake wheel cylinders located at the top between the front and rear brake shoes can leak. If they are leaking, you will see wetness near the ends of the cylinder. If that's the case they need to be rebuilt or replaced. Now is a good time to check and see if the axle seals are leaking too. Leaking axle seals or bearings must be replaced or the brake rebuild will be a waste of time and money. If either the wheel cylinders or axle seals have been leaking, your brakes won't have been working very well or possibly locking that wheel under hard braking.

Assess
Our Buick GS was in pretty good shape. The wheel cylinders look like they had been recently replaced and the axle seals were intact. The brake shoes had lots of material left but the drums were heavily scored and didn't look that good. Someone must have done the last brake job without turning down the surface of the drums. And this is an important step to make sure the drum surface is totally round and the braking surface is smooth and clean. One obvious item on the Buick was that the small brake parts such as brake shoe anchor pins, return springs, and spring seats were pretty beat-up and had never been replaced.

Tools
We made a plan of attack. First we got the brake drums turned at our local parts store ($20 labor charge). Next we purchased a small parts kit that comes with enough springs and anchor pins for both brakes (about $6). We purchased a set of new brake shoes because the others were heavily scored ($10 total!). And finally, we purchased a couple of cans of spray brake cleaner, a rotary wire brush for the cordless drill, some semi-flat black paint and a small container of gray cast-iron high-temp paint from a restoration company.