BRAKE FLUID AND BRAKE BLEEDING SYSTEM

Hello automotive friends, in this article we will share information about the automotive world. This article discusses brake fluid and bleeding brake systems, we hope that this article can help and increase the knowledge of friends in the automotive world. happy reading and learning.

Specifications for all automotive brake fluids based on Department of Transportation (DOT) standards must have brake fluid quality specifications such as:

* Free to flow at low and high temperatures.

* Boiling point greater than 400 degrees F (204 degrees C).

* Low freezing point.

* Non-corrosive to brake metal or rubber parts.

* Ability to lubricate metal and rubber parts.

* Hygroscopic (Ability to absorb moisture entering the hydraulic system).

The three brake fluids currently according to DOT are DOT 3, DOT 4 and DOT 5. DOT 3 and DOT 4 are a mixture of polyalkylene-glyco-ether while DOT 5 is based on silicon.

Precautions should always be observed when working with brake fluid:

* Brake fluid is toxic to the human body.

* Brake fluid can damage painted surfaces.

* Brake fluid contaminated with moisture, dirt, petroleum or other foreign substances will damage the internal hydraulic system.

* Only denatured alcohol or other approved cleaners should be used when cleaning brake fluid on parts of the hydraulic system.

* Use clean brake fluid (never reuse old brake fluid).

* Never mix brake fluid with other fluids, including types of brake fluid (for example DOT 3 and DOT 4).

1. Selection, handling of Brake Fluid and saving brake fluid.

To prevent contamination, the brake fluid should not be exposed to open air, the brake fluid container must be tightly closed and clearly marked.

ATTENTION:

* Moisture is very harmful to brake fluid, which can lower the boiling point of brake fluid, which can have serious consequences.

* Brake fluid is poisonous to humans and animals. Never store brake fluid in a way that might be mistaken for food or drink.

* Do not make air holes in the brake fluid container.

* Do not store brake fluid in extreme heat or cold.

* Do not store brake fluid for more than one month. Brake fluid can easily become contaminated with moisture if stored for a long time.

2. Handling brake fluid.

ATTENTION:

* Ingesting brake fluid causes illness or death. If brake fluid makes contact with the eyes, blindness is possible. Avoid contact between brake fluid and skin.

* Brake fluid can damage car paint and other finishes.

* Do not reuse brake fluid.

* Do not allow brake fluid to accumulate in large quantities.

* Immediately and safely dispose of contaminated or even suspected brake fluid to be contaminated.

3. Choose brake fluid.

Always choose high quality. Avoid "cheap" brake fluid. Do not skimp or cut the compass when handling the brake system. Brake fluid must meet or exceed manufacturer specifications.

4. Procedure for adding brake fluid.

ATTENTION:

Follow the proper procedures when adding brake fluid to the brake system to avoid injury to technicians and damage to the brake system.

* Park the vehicle on a flat surface.

* Carefully clean all dirt from the master cylinder cover.

* Remove the master cylinder cover.

* Make sure the fluid in the reservoir is clear and clean. If the liquid has a rusty or milky appearance, drain, rinse, and blend the brake system.

* Add fluid to the system to this level in 1/4 at the top of the reservoir.

* Restores the shape of the cover diaphragm. It should have no holes and be in good shape.

* The diaphragm may have become soft due to contaminated fluid.

* Put back the cover.

* Inspect the vehicle to ensure that no brake fluid has been spilled or thrown on the painted surface. Use soap and water to remove brake fluid from any painted surfaces.

5. Bleed the master cylinder.

It is a good idea to bleed the master cylinder after servicing and before installing / reinstalling the vehicle. One method of bleeding the master cylinder requires two brake master cylinder pipes and directing them back to the reservoir.

Fill the reservoir with clean brake fluid and slowly push the piston on the master cylinder several times until the air bubbles are no longer visible. This procedure will save time and fluid when bleeding the hydraulic system.

6. Basic bleed brake hydraulic system.

Whenever the hydraulic brake system is opened into the atmosphere for repair or because of a leak, the system must be bled to expel air. Unlike brake fluid, air is compressible and can result in a supple brake pedal and ineffective brake application.

The two most commonly used methods of brake bleeding:

a. Bleed with pressure.

b. Bleed manually.

a. Bleed with pressure.

A special device divided into two chambers by a rubber diaphragm. the upper chamber is filled with clean brake fluid while the lower chamber is filled with compressed air. The rubber diaphragm separates brake fluid from the air. Pressure bleeding is the preferred method for bleeding the brake system because one person can do the work alone and the master cylinder does not have to be refilled repeatedly during the process.

To bleed the brake system using the pressure method, first fill with clean brake fluid and fill the reservoir with 15 to 20 psi (105-140 kPa) of air. Fill the master cylinder reservoir to the proper level, usually about a quarter (1/4) inch from the top. Install the tool adapter into the master cylinder reservoir, attach the hose from the pressure tool to the adapter, and open the supply valve. Attach the hose to the cylinder wheel into a clear glass container partially filled with brake fluid. Open the valve and any air trapped in the system can be seen as bubbles coming out of the hose. Close the valve when all air bubbles have cleared. Repeat the bleeding process for all four wheels.

b. Bleed manually.

Manual bleeding of the brake system requires two technicians and the fluid level in the master cylinder should be checked frequently. Technician 1 aims to press the brake pedal to build up fluid pressure, then continues to maintain steady pressure on the brake pedal while technician 2 opens the bleeding valve and observes the brake fluid and air bubbles being released.

The brake pedal will reach the floor and technician 1 will continue to press the brake pedal until technician 2 closes the bleeding bolt. This process is repeated until all the air has been removed. Repeat the process for all four wheels. Check and refill the master cylinder when this procedure is complete.