Daily Maintenance of Cummins diesel generator set

Regular maintenance and regular maintenance and overhaul can timely discover and correct existing abnormal phenomena, eliminate hidden troubles, and prolong the service life of the unit, which is very necessary for the safe operation of the unit and the prevention of accidents.
1. Daily maintenance and maintenance
1.1 Check diesel oil, cooling water and oil, and add if necessary
1.2 Check for oil seepage, water seepage, air leakage, etc.
1.3 After starting the unit, listen to whether it is running normally (such as abnormal bearing noise, metal knocking sound, metal friction sound), and observe the instrument
Whether the working condition and the operation of the unit are normal
1.4 Be careful not to let the generator get wet, and do not let oil, water or other debris enter the inside of the generator
1.5 Check the drive belt weekly
Check the belt for tangential cracks, transverse cracks are acceptable. Longitudinal cracks intersecting transverse cracks are not acceptable. If the belt is chipped or damaged, replace it.
1.6 Check the cooling fan weekly
Check the cooling fan for cracks to make sure it is securely installed. Replace the damaged fan.
1.7 Lubricant and filter replacement cycle
Use only high quality lubricants (15W-40, API-CH-4 grade) and Cummins approved Fleetguard filters. For selection of lubricating oil suitable for local temperature, refer to your engine operation and maintenance manual. The maximum recommended oil and filter change interval is 250 hours or 3 months, whichever comes first.
If a single-component lubricant is used, the replacement interval is 200 hours.
Note: Do not allow dirt to enter the lubrication system when changing the filter element and oil.
1.8 Replacement period of fuel and fuel filter
Cummins recommends high quality and proper diesel and Fleetguard filters. The maximum recommended replacement interval for the fuel filter element is 250 hours or 3 months.

Note: 1) When replacing the filter element and refueling the fuel tank, be careful not to let dirt enter the fuel system.
2) The fuel tank must be cleaned regularly.
3) Do not use low quality, non-Fleetguard filter elements, otherwise it may cause serious early wear of the fuel pump.

1.9 Check the intake system and air filter weekly
Check the intake pipe for cracks and loose tubes. When the air intake resistance reaches the specified maximum allowable air intake resistance, replace the air filter element or clean the air filter element as required by the manufacturer.
Note: Even a small amount of dirt entering the engine will cause severe wear on the piston rings and large exhaust. Make sure the intake system is clean and leak-free.

1.10 Starter motor and battery
Make sure the battery wiring is clean and tight. The time interval between consecutive starts must exceed 2 minutes. Each start time cannot exceed 30 seconds. The battery must be charged regularly, and attention should be paid to keeping the battery warm in winter.
For more guidance and information, please refer to the “B Series Diesel Engine Operation and Maintenance Instructions”.
2. Maintenance of the generator set
In order to ensure the best performance and reliable working condition of the generator set, regular maintenance and inspection is the easiest and most economical method. Adhere to the maintenance, inspection and recording at the prescribed time. Maintenance and inspection work should be assigned to technicians who are familiar with the generator set and have certain experience.
The maintenance interval will be affected under the following strict operating conditions:
●Severe ambient temperature
●High salt spray area
●High dust and sandstorm area
●High chemical pollution
Therefore, try to make the unit run in a clean, tidy, dust-proof, rain-proof and normal temperature environment as much as possible.
There is no warranty if the equipment is not properly maintained. When carrying out equipment maintenance and inspection, you must pay attention to safety. When carrying out equipment maintenance and inspection, you must cut off the main switch of the battery power supply.
When repairing alternator electrical connections, engine or control panel, accidental starting of the alternator can cause personal injury
Injury or death of personnel, therefore, the battery power main switch must be in the OFF position during maintenance.

Before maintaining the battery, please confirm that the battery storage area is well ventilated. Any spark may ignite the hydrogen released by the battery and cause serious injury to personnel. It is generated when the connected and conductive tool touches the positive (+) pole of the battery and the generator frame or other grounded metal objects, so when repairing, be sure to keep in mind that the negative (-) pole wire of the battery must be disassembled first – after installation order.

The explosive gas of the battery can cause very serious injury to the human body.
No smoking.

Sparks or explosions can burn fuel and cause injury or death, do not put any fire
flames, cigarettes or other sparks near the fuel system.

Do not start the engine when the oil level is above the low or high scale. Too much oil can cause gas
Foaming or mixing of oil and gas, operation at low oil level will cause the oil pressure to be too low.

The pressure in the crankcase may eject hot oil and cause severe burns, so the generator set is running
, do not check.
Chapter VI Common Faults of Unit and Remedy Methods
1. Troubleshooting and troubleshooting
The generator set has many sensors, which can continuously monitor the operation of the generator. When abnormal conditions occur, such as low oil pressure of lubricating oil, high temperature of coolant, etc., a warning will appear on the control panel. If there is an overspeed, the generator set will protect parking. When a fault occurs, please stop immediately, check the cause of the fault, and start the generator set again after the fault is eliminated.

High voltage can cause serious casualties, so be careful when troubleshooting.
When the generator set needs to be repaired due to a breakdown, be careful not to start the generator set unexpectedly. Put the operation control switch in the “stop” position, and throw the main switch of the battery power supply to the off position.

During troubleshooting, the generator set starts unexpectedly, which will cause serious casualties.
Safety measures must be taken.
When an error occurs, follow the troubleshooting procedure to find and correct the error. If the fault still cannot be eliminated, please contact the nearby sales service center or factory.

Persons without professional training should not attempt repair work, otherwise it may cause serious injury.
This troubleshooting material is intended for trained personnel only.
2. Please refer to the following appendix for the fault phenomenon and troubleshooting method.

Trouble phenomenon Trouble cause Solution
generator does not
Can generate electricity
1. Remanence disappears or is too low
2. Damaged voltage regulator
3. Wiring error
4. Damaged rotating rectifier
5. Main generator field winding or exciter field winding disconnection
6. Main generator stator disconnection
7. The generator burns out
8. The rotation speed is too low (below 1000RPM) 1. Use the battery to charge the magnetic field winding, the positive pole is connected to E1, and the negative pole is connected to E2
2. Replace the voltage regulator
3. Check according to the wiring diagram, correct wiring
4. Open the back cover of the generator and replace the components
5. Use a multimeter to measure the corresponding winding, if the resistance is infinite, it should be connected
6. When the resistance is infinity measured with a multimeter, the disconnection should be found and connected.
7. Replace the corresponding coil
8. Increase the speed of the diesel engine
No-load voltage is too low or too high 1. The speed has not reached or exceeded the rated speed
2. Partial short circuit of excitation winding (short circuit between turns)
3. The rotating rectifier is damaged
4. The voltage regulator is damaged 1. Adjust the speed to the rated speed of 1500RPM
2. The excitation current of the exciter is large, and the DC resistance of the excitation winding is much smaller (check with a bridge or direct current), and the coil should be replaced
3. Replacing components
4. Replace the AVR
The unit cannot be started or is difficult to start 1. The start button is broken and the starting resistance is large.
The battery is not sufficiently charged.
2. There is air in the oil circuit
3. The fuel does not reach the injector
4. The fuel injector is not working properly
5. The fuel supply circuit is not smooth
6. The oil pressure is too low 1. Replace the start button and replace the battery
2. Remove the air in the high-pressure oil circuit, insert the oil return pipe under the oil surface of the fuel tank, and install a fuel pre-filter.
3. Check whether the high-pressure oil pump has oil
4. Clean the injector or replace it
5. Check fuel pump and filter
Check oil level or sensor
Insulation resistance measurement is abnormal 1. The output main line is connected to the ground
2. Generator insulation damage 1. Check and eliminate section by section
2. The generator is insulated
3. Troubleshooting of the generator set controller
Symptom Possible Action
Controller does not work Check starting battery
Check controller wiring
Check DC Insurance
The unit is shut down Check whether the water temperature is too high
Check alternator voltage
Check DC Insurance
Controller emergency stop locked Check emergency stop button function is correct
Check that the positive starter battery is properly connected to the emergency stop input
Check the wiring for open or short circuits
Low oil pressure alarm after successful start Check oil pressure alarm or sensor and its connection
High water temperature alarm after starting successfully Check the water temperature alarm or sensor and its connection
Alarm and stop during operation Check the relevant switches and connections according to the LCD display information
Check programmable inputs
Unsuccessful starting Check the actuator and its connection
Check fuel
Check the starting battery
Check the speed sensor and its connecting wire
Consult the engine manual
Starter does not work Check starter connection
Check the starting battery

In case of failure, please professional and technical personnel for overhaul, or contact the manufacturer by phone.
The replacement of electrical components must use electrical accessories of the same model and nationally certified and licensed manufacturers. You can also call the manufacturer to solve it.
Replacement engine parts must use original Cummins parts.