There are many types of excavator engine malfunctions, so what causes engine speed drop during excavator operation? And how should it be resolved?
As the name suggests, engine speed drop refers to a decrease in engine speed during excavator operation. This speed drop manifests in two ways: a slight drop within 200 RPM, and a severe drop above 300 RPM, which can potentially cause the excavator to stall suddenly.
The main causes of excavator engine speed drop are as follows:
1. A fault in the excavator’s diesel fuel system. Generally, a blockage in the diesel fuel system can cause speed drop.
2. A fault in the excavator’s hydraulic system, preventing the hydraulic pump from properly adjusting its displacement, resulting in excessively high system pressure, speed drop, and possibly engine stalling.
3. Insufficient engine output power, with output power below rated power and excessively low speed. A problem with the main pump is also a cause.
4. Using poor-quality fuel or fuel with excessive water content can lead to insufficient engine power and a drop in speed.
5. Air leaks or blockages in the intake system can cause insufficient air supply to the engine, resulting in incomplete combustion and causing a drop in speed and black smoke.
6. Excessive solenoid valve clearance can lead to insufficient fuel supply, causing the engine to drop in speed.
7. Loose fuel supply circuit connectors or broken pipes can cause fuel leaks or blockages, leading to insufficient fuel supply and potentially causing stalling in addition to a drop in speed.
8. There are many other causes of speed drops, such as incorrect valve clearance, incorrect fuel injection timing, a damaged turbocharger, or faulty brakes.
Having discussed so many causes of excavator engine speed drops, what should be done when this occurs?
1. First, check if the diesel fuel used by the excavator is contaminated or contains impurities, and check if the fuel lines are blocked.
2. Check the valve clearance of the excavator engine and check the engine speed.
3. Inspect the intake manifold, clean the air pre-filter and air filter element, then restart the engine.
4. Check if the excavator’s speed drop occurs under engine load.
5. Conduct a thorough inspection of the engine to determine if an engine malfunction is causing the speed drop.
6. Additionally, the electronic control system, hydraulic system, fuel system, etc., also need to be checked.
