- Practical advice
- Provide reliable tools
- Clean as you go
- Purge after reassembly
- Disassemble the wheels
- A new brake master cylinder
To reduce the cost of maintenance of a car, you can do some work yourself, while respecting the safety rules. Example with the change of the drum brakes of a Twingo.
• If you are not working on a flat concrete surface, use pieces of planks or flat stones so that the jacks or candles used are as effective as on hard, flat floors.
• As you dismount, take the time to clean the parts with a brush or a dry cloth. Avoid compressed air that scatters particles.
• Protect new upholstery from dirt (grease, oil, dust, etc.) until the drums are put back in place.
• In order to avoid certain errors when reassembling, proceed wheel by wheel, keeping the other assembly as an example.
• When purging, think of the environment: carefully collect the brake fluid for disposal in a service station, or put it back into the brake system.
On an automobile, some malfunctions, such as the braking system, must be repaired. This is the case on Twingo, aged a dozen years and equipped with drum brakes (rear). Rather than trying to get them fixed, his owner preferred to change them.
Provide reliable tools
It is not necessary to have a bridge or a pit to change such a system of brakes, but it is important to provide appropriate tools. Two adjustable candles and two jacks are a minimum to lift the vehicle and work safely. Two tools are essential: a cross-shaped wrench to unscrew the wheel bolts and a 30 mm socket for unblocking the drum's central nut. Disassembly is done with the handbrake loosened and the loosening of the bolts and the nut causes the wheel on the ground.
Clean as you go
Disassembly of the gaskets begins with the removal of the bearing springs and their bolts by unscrewing while pressing, so as to compress the springs. The last operation is to unhook the handbrake cable using a pair of pliers. The toppings are released by spreading the upper and lower beaks. It is then possible to remove the master cylinder to be replaced by unscrewing the two outer retaining nuts and the brake fluid inlet line. At this point, it is important to clean the remaining parts. The rust and materials that have been deposited over the years do not mix well with new parts.
Purge after reassembly
When all parts and wheels are reassembled, it is necessary to purge the system to remove air bubbles in the circuit. On the Twingo, the brake fluid reservoir (Lockheed) is located on the right under the hood. It is necessary to begin to purge the furthest wheel (here rear left, then rear right, front left, and to finish right front) so as to drive out the air as and when. Last important detail, do not press the brake pedal for the duration of the operation. Once the purge is done, it is important to ride a good time with the vehicle to test the effectiveness of emergency braking several times and honing new parts.
Disassemble the wheels
Loosen the four screws, without removing them, then the big central nut using the cross. Position the cross well in front of the bolt axis for increased efficiency.
Once the drum is removed, we notice that the brake lining is peeled off. The fault is updated! Remove the trim by releasing the upper and lower beaks.
Using a pair of pliers, carefully unhook the parking brake cable. This gesture will allow you to permanently separate the trimmings in order to replace them.
A new brake master cylinder
After removing the old master cylinder, reverse the procedure to reposition the new cylinder by tightening the two nuts and supplying the brake fluid.
Put the new packing in place by positioning the jaws of the jaws on each side of the cylinder, then support them on the lower stop while evacuating the spacer (green) in PVC.
Proceed with the installation of the transverse nut from stalling the assembly. The support spring is held in place by a safety cap that is put in place with a pair of pliers.
To replace the drum, leave two of the wheel clamps in place. They will serve as a handle and help you to house the drum in its location.
Loosen the bleed screw a quarter of a turn. Pump the brake pedal until the fluid drains from the bleed, without bubbles. Then tighten, brake pedal depressed.