How to Deal with the Alarm and Speed limit of 1400RPM when the Doosan Excavator Engine is Working

This article mainly introduces how to deal with the problem of alarm and speed limit of 1400RPM when the doosan excavator engine is working.

 

2023.07 Doosan DMS-5 Data Monitoring System Diagnostic Software

Fault phenomenon:

An alarm occurs during engine operation and the speed is limited to 1400RPM. 

 Inspection Method: 

 1) The vehicle has been working for 2200 hours, the equipment speed limit is 1400rpm, and the fault code retrieved is P1251: fuel balance leakage;

2) Check that the low-pressure oil line pressure is 70kpa, which is on the low side (normally around 90kpa); after cleaning the oil-water separator, the low-pressure pressure has increased, but the fault still occurs from time to time;

3) After low-pressure inspection, check the high-pressure system, connect the software to perform cylinder disconnection test and crankshaft acceleration test. There is no obvious abnormality in the working status of each cylinder;

4) Check that the resistance of the IMV valve is 3.2 ohms and is normal. Since the IMV valve is easy to disassemble, the 2018-04-27 13:49 Wang Xiaobo IMVi valve was replaced first and tested. After replacement, the equipment works normally.  

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When the P1251 fault code occurs in the engine, the casing should be arranged from simple to difficult. First, check the low-pressure fuel oil line, and then conduct troubleshooting of the high-pressure well rail system.