Mercedes C230 Owners Manual

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April 11th, 2010 admin Leave a comment Go to comments

A Reliable Braking Aid in a Mercedes Benz Brake Booster

In critical situations, every centimeter counts. It is for this reason why the modern automotive brake system has been refined for over 100 years and has become highly dependable and efficient. This is also the reason why Mercedes Benz's braking system has been designed to take account of model-specific factors such as aerodynamics, Anti-Lock Braking System (ABS), bodywork, chassis and engine. Acting as the heart of this braking system is the Mercedes Benz Brake Booster.

The Mercedes Benz Brake Booster is mounted on the firewall directly behind the master cylinder and, along with the master cylinder, is directly connected with the brake pedal. Its main purpose is to amplify the available foot pressure applied to the brake pedal so that the amount of foot pressure required to stop is minimal. The Mercedes Brake Booster acts as a C230's “power brakes.” Without this booster, considerable amount of force is needed to manually bring the brake fluid to each wheel, putting a lot of pressure to a foot. Practically speaking, a Mercedes Brake Booster enables the vehicle to stop without having to use a significant amount of force.

How does the Mercedes Benz Brake Booster work? Brake fluid is added to the cylinder and the booster is the vacuum source. When the driver steps on the brake pedal inside the vehicle, vacuum from the brake booster forces the brake fluid inside the master cylinder to each wheel. The booster gets its vacuum from the engine via a rubber hose. Power for the booster comes from engine vacuum. The automobile engine produces vacuum as a by-product of normal operation and is freely available for use in powering accessories such as the power brake booster. Vacuum enters the booster through a check valve on the booster. The check valve is connected to the engine with a rubber hose and acts as a one-way valve that allows vacuum to enter the booster without letting it escape.

The Mercedes Benz Brake Booster is an empty shell that is divided into two chambers by a rubber diaphragm. There is a valve in the diaphragm that remains open while the foot is off the brake pedal so that vacuum is allowed to fill both chambers. When one steps on the brake pedal, the valve in the diaphragm closes, separating the two chambers while another valve opens to allow air in the chamber on the brake pedal side. This process provides the power assist. Power boosters are very reliable and cause few problems of their own. However, other things can contribute to a loss of power assist. In order to have power assist, the engine must be running. If the engine stalls or shuts off while driving, one will have a small reserve of power assist for two or three pedal applications. After that, the brakes will be extremely hard to apply and lots of pressure must be put to bring the vehicle to a stop.

There is a weak spot in the Mercedes' Brake Booster – it is made up of large rubber diaphragm. The brake booster may crack and leak as the rubber ages. An obvious sign of this is when the driver finds himself pressing his feet as hard as he could to stop his Mercedes Benz as a result of lack of vacuum to assist the braking. Mercedes Benz Brake Booster usually develops small leaks before a total failure takes place, giving enough time for a replacement, so maintaining this part does not give big-time headache to the owner.