Brake Fluid Handling Precautions
The hydraulic clutch uses brake fluid, which is toxic, so the following precautions must be observed before any work is done on it.
Brake fluid should be stored in a special container with the appropriate designation. The liquid is poisonous, even 100 ml of liquid can cause death.
Use gloves and goggles to protect skin and eyes. In case of contact with skin, wash immediately with soap and water. In case of contact with eyes, rinse immediately with clean water. Seek medical attention if necessary.
Do not allow brake fluid to come into contact with painted vehicle surfaces. In case of contact, rinse immediately with clean water.
Brake fluid is hygroscopic; when moisture is absorbed, the boiling point of the fluid decreases. For this reason, it must be stored in a tightly closed container.
If even a small amount of mineral oil gets into the brake fluid, the rubber hoses of the hydraulic system can be damaged. It is especially difficult to notice oil ingress when using colorless or yellow brake fluid. If oil enters the system, it is necessary to replace the reservoir, the clutch master cylinder and all rubber parts of the brake system. Then flush the system with fresh brake fluid and bleed. Given these consequences, be careful not to let oil enter the system.
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Pic. 182. Location of the clutch master cylinder: 1 - return spring; 2 - spring cup
On fig. 182 shows the location of the master cylinder. When removing, do the following:
- remove the upholstery under the instrument panel on the left side;
- remove the rug from the floor on the left side;
- to avoid leakage of working fluid from the system, the outlet hose from the master cylinder can be clamped with a suitable clamp. Otherwise, while pressing the clutch pedal, drain the fluid from the system through the bleeder of the working cylinder and the drain hose into a special container;
- remove the outlet hose from the master cylinder;
- disconnect the brake light switch connector;
- unscrew the master cylinder from the clutch pedal bracket;
- take the clutch pedal away, disconnect the spring, its protection and the washer from the pressure rod;
- use circlip pliers to remove the snap ring securing the pressure rod (at the top of the clutch pedal);
- remove the connecting hose with the tip from the cylinder and remove it.
Installation of the master cylinder is carried out in the reverse order. Be sure to pay attention to the correct installation of the tip of the connecting hose. When connecting the pressure rod, its end with the flange must point towards the pedal. Check that the circlip is properly seated in the groove. After completion of work, bleed the clutch drive (see subsection 6.8).