Excavator: How to adjust the hydraulics?


If the excavator can not be finely controlled or reacts nervously, this always indicates a problem with the hydraulics. How to adjust the hydraulics of the excavator, when to set it and when other causes are responsible for it, read in this article.

Adjustments necessary?

Basically, you do not have to worry about the hydraulics and their settings for rented excavators. Such work is always done by the landlord.

Anyway, you only have to worry about the attitude if you have bought an excavator.

If massive changes occur during operation ("nervous" behavior, control can not be finely regulated) is more likely to suspect that there is a defect in individual small parts than actually a misaligned hydraulics.

In such a case, you should definitely give the excavator for repair and have the faulty parts determined and replaced. As a rule, these are only very small parts - such as the neutral spring on the slide or a brake valve.

hydraulic pressure

The hydraulic pressure should not exceed certain values. The pump itself is responsible for the pressure itself, depending on how much pressure it exerts (at idle and below rated speed), the so-called pressure limiter (DBV) must work more or less.

It measures the prevailing pressure based on a characteristic curve and, if the pressure is too high, causes the excess oil to run back into the tank, causing the pressure to drop again. The pressure limiter valve can be adjusted - then the incoming pressure of the hydraulics is higher than it should be.

However, such cases are extremely rare - as a rule, a setting on the pressure limiter was changed so that it only reacts later.

Smaller increases, even if the pressure limiter is set correctly, can be expected if the pump is replaced by one with a significantly higher flow rate. In this case, something may need to be readjusted on the DBV.

Tips & Tricks

If you notice changes in control behavior, you should always get to the bottom of it. Damage that you notice and correct early on is often much less expensive than subsequent major damage.


Video Board: Excavator Main Hydraulic Pump Receiving Pressure & Flow Rate Test