What are the reasons for excavator speed drop introduced by the accessories manufacturer of Shengang excavator?

2025-06-13

1. Some cars use solenoid valves (fuel interceptors) to control the oil circuit to cut off fuel, thereby achieving the intention of stalling.

I have encountered a similar problem before, where the clearance between the solenoid valve is too large, like the effect of pulling half of the flame out wire, causing a lack of fuel supply due to the load, resulting in a decrease in speed, which leads to a lack of fuel supply in the diesel pump. This is a vicious cycle, ultimately leading to flame out. Liugong excavator accessories will not have this situation.

2. The impact of temperature is relatively small, after all, there are cooling devices, and the environmental impact is mainly on air pressure. For high-altitude areas, the air is thin, the oxygen content is low, and imported excavator parts and engines lack combustion, which affects engine performance. However, air superchargers also reduce the impact of high altitude.

The main reason for engine deceleration is still the change in load. When the hydraulic system malfunctions and the displacement cannot be changed, it can easily lead to deceleration or stalling.

3. There are two main reasons for the speed drop: decreased engine performance and problems with the main pump. Check the engine and main pump.

You can first remove the hydraulic filter element and take a look. If there is a lot of copper powder on the filter element, it means that there is a problem with the main pump and it needs to be overhauled.

You can also enter the monitoring panel to check the engine speed. The minimum throttle idle speed is over 1000 rpm, the maximum throttle idle speed is over 1300 rpm, and the maximum throttle idle speed during operation is over 1900 rpm.

If there is no copper powder and the engine speed is normal, removing and cleaning the two solenoid valves on the main pump can basically eliminate the problem.

4. If the output power of the engine is significantly lower than the rated power, then the simplest way to determine it on the construction site should be started.

Firstly, check if the fuel filter is blocked, if there are any air leaks in the fuel path, if the plunger, fuel injector, and outlet valve in the fuel pump are severely worn, if the air filter intake is unobstructed, if the engine with a turbocharger is damaged, if the engine is running at high temperatures, if the oil viscosity is decreasing, if the cylinder wall is not tightly closed, if the cylinder liner components are worn, if there is severe air leakage in the cylinder, if the engine valves are not tightly closed, etc. These are all factors that seriously affect engine power.