Adjusting clearance

Cars E-Class are equipped with control clearance (clearance), which allows the rear of the car is constant ground clearance, regardless of load. Thus, even when fully loaded or when towing a trailer full of luggage and driving characteristics are not impaired, which has a positive impact on active safety. On vehicles equipped with control clearance, the oil pump controller is installed directly behind the power steering pump. Sometimes there is called "tandem pump" as both pumps are driven by a single shaft. Pump regulator clearance pumping hydraulic fluid from the expansion tank and with an appropriate resistance can create a pressure of up to 200 bar. Further, the working fluid pressure supplied from the pump to the pressure regulator on the rear suspension. The controller is connected to the rear stabilizer - so defined by loading the vehicle. Depending on its regulator opens or closes the working fluid for the respective valves.

The following operating states control clearance:

1. Filling. When a heavy load vehicle control lever is moved to the upper position, and the hydraulic fluid is supplied to the storage tanks on the strut. The rear of the car is lifted until the lever again occupies a middle position. If the load is so large that the arm is not returned to the initial position, relief valve limits the pressure in the racks at the level of 150 bar.

2. Drain. In this case the control lever is in the down position. If the rear of the car is unloaded, the working fluid flows back out of the rack into the tank, the rear part of the machine is lowered. In the stands, however, there remains a pressure of 30 bar for damping function.

3. The middle position. The working fluid is almost no pressure coming from the pump through the regulator to the tank.

Check regulator clearance

1. Check the fluid level in the tank - it is located in the engine compartment on the left and also provides power steering. Under normal loading of the car level must be between the ?�MIN?� and ?�MAX?�.

2. For the topping, use oil for hydraulic system (take on the company's stations MOT). Use the liquid in the tank specified: Oil hydraulic drive system Zentralhydraulikoel (Nr. 000 989 20 03/10 for one liter containers).

3. In the regular fall of the liquid level in the tank, check pump, controller, storage tanks on stands, shock absorbers. With the engine running place to detect leaks easier.