Drum brake is not much in use in the modern day vehicles. The braking capacity of these brakes is only around 25% in the vehicles in which it is used. Most of the vehicles now have ‘four-wheel disc brakes’. Some of the vintage cars had the ‘four-wheel drum brakes’, but the drum brakes were not as responsive as the disc brakes. As it controls only around 25 percent braking capacity, the disc brakes at the front, control and are responsible for the braking. However, if these disc brakes do not respond, the drum brakes compensate for their action and help control the bike. If the braking is completely dependent on the front brakes, then the disc brakes spoil easily. The rear drum brakes if kept in good working condition, it will not overload the front disc brakes. You must thus know how to adjust drum brakes so that the braking system is balanced and the front brakes do not wear out fast.
You will need a couple of things to adjust the drum brakes. To help you with it, refer to the list given below:
- Jack Stands
- Floor Jack
- Lug Wrench
- Brake adjustment spoon
- Socket Set and Extension Set
- Repair Manual
- Penetrating lubricant
- Long Screwdriver
Most of these things would come along a vehicle repair kit. If you have one such kit, check it for all these instruments
How to adjust drum brakes?
- To start with this procedure, you will first have to detach your vehicle’s rear wheels hub cap. Loosen the lug nuts using a lug wrench.
- Using a floor jack, lift the rear portion of your vehicle upwards and let it stay in the same position using the car jack stand.
- Detach the car wheels by removing the car nuts.
- After removing the wheels, look for the car’s adjusting porthole. It is located on the rear side of the car’s backing plate. A rubber plug caps the porthole as a protective cap and saves it from all foreign elements. Using a screwdriver, pry the plug outwards and remove it.
- Using the long screwdriver, you need to locate the ‘adjusting retainer clip’ by inserting the screwdriver in the porthole. You can also use a flashlight while you go beneath the car, to locate the retainer clip. The clip looks like a tiny lever holding the car’s star wheel at the right position. Depress the clip in the opposite direction from the wheel with a screwdriver, and using an adjuster for brake spoon, start turning this star wheel in the opposite direction.
- Next, start spinning the drum with your hand. As you spin this drum, the brake tension increases and you are just adjusting it the right way. If the brake tension decreases and the drum starts spinning freely, you are not adjusting but un-adjusting the brake. For this, you will have to again go back to the car’s star wheel, and using a spoon, turn the wheel in opposite direction.
- While making these adjustments, occasionally pull the car’s parking cable located near the hind side of the car’s backing plate, and try moving it towards the center of the brake shoes.
- While adjusting the brake shoes, keep checking the tension on the brake shoes as compared to the drum. To check this you can spin the drum and check for the tension. While spinning the drum, it should move, but you should feel that the drum is being dragged away from the brake shoes touching the inner diameter of this drum
- To stop the drum from completing one full revolution by itself, adjust the shoe brake upwards.
- When you are done with one side, repeat it again for the other side as well.
- After this, get inside your car and simultaneously apply the parking brake and brake pedal. This will lead to integrated mechanism of the parking brake.
- Next step is applying the parking brake and letting it go, still on the same position. At the same time, check the position of the rear drums. If one drum is holding rightly and the other drum is not, then look for the parking brake cable’s equalizer. Adjusting this equalizer will hold the drums in positions. This equalizer adjustment is given in the user’s manual of your car, and you have to adjust it accordingly.
- Next will be pumping the brake pedal foot and applying parking brake again simultaneously. While doing this adjust the equalizer if needed.
- After the tension on the brakes is correct and the holding is right, place the car’s porthole plug back and replace the car wheels. Tighten the lug nuts. Check all the wheel lug nuts before taking your car for a test drive.
- It is mandatory that you test drive your vehicle once you are done with these adjustments.
Do not directly take your car on road. It might lead to a fatal accident if any of the part is not placed properly. A test drive is must to check the functioning.