Time for a ‘mourning’ break?
When you are driving your old LaSalle or Cadillac down the road and you need to apply brakes, either for a regular or panic stop, you have the right to expect a smooth, even stop.
How quickly you stop should depend on how hard you push the brake pedal. When this doesn’t happen, you experience the same effect as a triple dose of milk of magnesia — only quicker.
Hopefully, since last month you have rebuilt your brakes or have determined that your braking system is in good condition and only needs adjusting. If you have installed new brake shoes and/or turned the drums, you should readjust them after a couple hundred miles and they are “broken in.”
The adjusting of new brakes or older brakes is basically the same procedure, with a few exceptions. A few minor details we will cover as we go along. Let’s also assume you are going to do it right.
Start out by jacking up all four wheels and put the car on stands. If you have new brakes, everything should be clean…otherwise the first thing to do is a thorough cleaning.
Let’s get started—it will be much easier if you remove all four wheels, but not the drums (this is a good time to rotate your tires, too.)
Start off by either disconnecting your emergency brake cable at the “Y” under the center of the car, or at least loosening it to where each rear cable is loose and sagging. At this time, squirt a little penetrating oil where the cable goes into the sheath where it connects to the rear frame near each rear wheel.
Work each cable back and forth until it is free and wipe off any excess oil that could collect dirt. Loosen the adjusting star wheel all the way. Usually this means an upward movement of the star wheel. This will make removal of the drum much easier.
Now take off, starting at the right rear. Take off the drum and start cleaning, first with compressed air blowing away all brake dust. You should wear a filter mask when doing this, as some older shoes were made of asbestos.
Next, you will want a couple of cans of “brake and electric cleaner” on hand and wash down all components thoroughly, including the inside of the drum and the faces of the brake shoes. Wipe down and blow off with compressed air. Inspect all parts.
If the shoes are worn down and/or you have grooves in the drum, it is time to go to last month’s article and rebuild the brakes. It is not uncommon to find that the front brakes have been relined three times and the rears have never been relined. There are two reasons for this: First, the front brakes wear out three times quicker than the rear ones and the rear drums are five times harder to get off (usually).
If you do have to reline one rear brake, always do both sides. The same applies to the front, however, not true as far as front to rear. Make sure the emergency brake mechanism is operating freely; and a little squirt of penetrating oil in the front of the sheath worked back and forth will help, but make sure all excess is wiped off.
Any type of oil, grease or brake fluid on the shoes or drums is real bad news. If there is any sign of brake fluid in the brake mechanism, you need to replace or rebuild the wheel cylinder. You might note that if you have axle grease in this assembly, you should replace the seal (see your shop manual).
The top anchor pin at the top of the brake shoes is actually an eccentric pin and is a very important adjustment. It is held in place by a lock nut on the rear of the backing plate. You will notice this anchor pin is adjustable from the rear of the backing plate and formed in a manner that indicates the “high side.”
If worn off or not visible, mark it with a center punch or white crayon. Then loosen this locking nut and make sure it can be rotated freely and return it to the position it was prior to loosening, but do not tighten at this time.
With the star adjusted all the way down, you are ready to put the drum back on and tighten the axle nut. The last thing before you put the drum on is to give the drum and lining a final cleaning with brake cleaner to remove any dirt from fingers, etc.
Now the wheel should spin freely. If not, adjust the eccentric until it does. If it still doesn’t spin free, your linings are too large and need to be arced down or you didn’t put it together right.
Back to the shop manual. Spin the wheel and start turning the star wheel until a show starts to rub—at this point, you are ready to start adjusting.
If the drums are on the other three wheels, step on the brake hard a few times. This should somewhat adjust your eccentric. Spin the wheel again and if you do not have the lining making contact, repeat the process until it still rubs slightly.
Now is the time to get out a .015 feeler gauge. You will find a small slot in the drum at the outer edge that will let you slide the feeler gauge between the face of the drum and the lining.
With the feeler gauge in place, rotate the drum to find the high spot. You can now adjust the eccentric anchor pin to a point as near as possible, tighten the lock nut on the anchor pin making sure you hold the adjustment in place with another wrench so you don’t move this very fine adjustment. Now adjust your star wheel to a point you have resistance when the feeler gauge is in place and the wheel turns freely when the gauge is out.
If you are adjusting old brakes, you should at this time bleed until it is clear and clean. Now you can go to the left rear wheel and repeat the process.
Doing the front wheels starting with the right front is basically the same except for the way the drum comes off. While the front drum is off, it is a good time to pack the wheel bearing. Do not overdo it. The spindle should only have a thin coating of grease.
The bearings should be packed with good grease and not the spindle cavity. Tighten down the spindle nut until you feel resistance and then back off the nut to the next slot where you can put in the cotter pin. Always use new cotter pins.
Now that all four brakes are adjusted, you are ready to adjust your emergency brake cables. With the cable still loose at the “Y”, you should be able to pull the emergency brake handle all the way up and still turn the rear wheels by hand. Work it a few times to make sure it is free for full travel. Lube where necessary to have free travel all the way.
When you have it operating freely, it is time to adjust. First of all, pull the brake handle two clicks and while in this position, get under the car and tighten up this adjustment to a point you start to feel the rear linings come into contact with the drums.
If your cables are stretched and you cannot adjust to this point, you may have to get some brake cable tighteners at your local parts or accessory store. Put your tires and wheels back on and spin each wheel, making sure you have no drag.
Have someone push the brake pedal slightly just to the point where you have slight friction; but don’t lock the wheel—make sure all four wheels are close to the same amount.
You should be ready to put the car on the ground for a test drive, or more accurately, a brake test. On your test drive, be sure to “drag” your brakes a bit to set them in. Don’t overdo it but drive about a block with slight pressure on the brake pedal. Let them cool down and do it again.
Well now, tomorrow you can enjoy a jelly doughnut with your morning coffee break, instead of mourning a bad roll because of a bad brake.
See ya next month.