Cooling
Engine overheats only under load
Normal unloaded temperature but rapid heating during digging/travel means cooling handles low heat output, not the engine's working heat load.
Radiators and airflow
A partly blocked pack may suffice at idle but not at work. Check coolant radiator, intercooler, hydraulic cooler, spaces between them, fan speed/command and airflow direction.
Thermostat opens only partly
Partial opening can appear normal without load but restrict circulation at high heat output.
Insufficient pump flow
A worn/damaged impeller may circulate coolant at low load but not meet full-power demand.
Hydraulics overloads the engine
Excess pump load can simultaneously drop RPM, create smoke and heat. Compare different functions and check whether the pump constantly operates at elevated pressure.
Fuel, air and exhaust
Incorrect combustion also increases heat. Check boost, air filter, EGR, DPF, injectors, fuel pressure and active derate.
Gases in cooling
A head gasket may leak gas only at high cylinder pressure under load while idle looks normal. Clues: coolant expelled after work, rapidly filling tank, hard hoses and worsening with load.
What to observe
Which work and how many minutes trigger overheating? Maximum fan response, hydraulic heating too, power loss, coolant expulsion and black smoke.
Related problems
Further service support
Problem still there?
If these checks have not identified the cause or the fault returns, contact TSV Servis. The more initial information you provide, the sooner we can identify the next diagnostic direction.
What to send us
Loaded engine/hydraulic temperatures, fan RPM/command, radiator condition, hydraulic pressure and exhaust/boost data.
Include the make and model, S/N or a nameplate photo, engine model if known, operating hours, exact code or display photo and when the fault occurs.
Also tell us what you have already checked or replaced and the results. Include a photo or short video of the symptom where useful.
+420 722 307 850 · tsvcz@seznam.cz