Excavator output is cycle time plus fuel per cycle. The hydraulic pump decides how fast the functions move. The injectors and ECM decide whether the engine can hold rpm while those functions are working. If either side is weak, production drops and fuel use rises.
Split the complaint
- Engine rpm falls and smoke appears: look at air, fuel, injectors, and the turbo
- Rpm holds but functions are slow: look at the pump, the valves, and the reliefs
- Both happen together: test before you buy either a pump or an injector set
Write down rpm under load and a simple cycle time. Those two numbers make a remote quote much more accurate.
We can supply the hydraulic and the engine side from the same enquiry if you include both serials.