How to solve the problem of alarm and speed limit of 1400RPM during operation of DL series engines
Doosan Diagnostic Tool UVIM Support Doosan Excavators High Quality
Model: DL series engine
Fault phenomenon: An alarm appears during engine operation and the speed is limited to 1400RPM.
Inspection method:
1) The vehicle has been in operation for 2200 hours, the equipment speed limit is 1400rpm, and the fault code retrieved is P1251: Fuel balance leakage
2) Check the low pressure oil circuit pressure, 70kpa, which is low (normal is about 90kpa); after cleaning the oil-water separator, the low pressure increased, but the fault still occurred from time to time.
3) After the low-voltage check, the high-voltage system was tested, and the software was connected to perform cylinder disconnection test and crankshaft acceleration test. There was no obvious abnormality in the working status of each cylinder;
Doosan Dms-5 Diagnostic Software with Troubleshooting v3.2.5 (04.2025)
4) Check the IW valve resistance, 3.2 ohms is normal. Since the IW valve is easy to disassemble, replace the IW valve first and test it. After replacement, the equipment works normally.
