Inspections before Operation and Maintenance
Check the insulated resistance:
An insulated resistance usually results in the creepage of the alternator when it is below the regulated value and then brings on the security problems.
The user should check the insulated resistance between the master and subordinate reels and the insulated resistance between the reels and the crust with 500V megohmmeter regularly.
Value should not be under 2 M ohms at normal temperature; otherwise these parts should be dried. Use the electric cooker, infrared ray or big bulb or something else to heat them up outside until the insulated resistance reaches the regulated value.
Check the alternator assembly: Make sure all the firming components are tight and the rotor is easy to turn by hand without impacting, scrubbing and any abnormal noise. Do not let the rain or other liquid drop into the alternator.
Starting the generator: The end of voltage output should be on before running the machine. Generator should self excite, generate voltage in gear and reach the rated power when engine speed is accelerated to the rated value. Otherwise, stop the machine and check it.
Preventive & Breakdown Maintenance of Diesel Engine
Keep generator away from the oil, vapor, acidic/alkaline gas, saline brume and do not let any other solid matter fall into the generator.
Keep drafty when the generator is running. Do not put anything on the surface of generator for baffling ventilation and heat dispersion.
Do not operate under over-loading condition continuously and inspect bolts and mechanical firming components routinely.
Checking Methods when the Engine Encounters Malfunction
| CAUSES | TROUBLESHOOTING |
| Speed sometimes fast, sometimes slow | Check if the speed governing system is flexible, and if air mixed in oil pipeline. |
| Abnormal noise suddenly sent out | Stop the engine and inspect each movable parts carefully |
| Exhaust with black suddenly | Check fuel system, especially the nozzle. |
| Rhythmically metal knocking sound in the cylinder | The fuel delivery angle is too big, should adjust the angle. |
Causes and Troubleshooting for Diesel Engine Stopping Automatically
| CAUSES | TROUBLESHOOTING |
| Malfunction of the fuel system
Run out of fuel |
Fill fuel. |
| Obstruction in fuel pip or air filter | Check or clean. |
| Air exists in fuel system | Emit the air. |
| Nozzle needle was bitted | Clean, skive the nozzle or change it if necessary. |
| Obstruction in air filter | Check, clean or brush off, or change the filter element |
| Sudden increase of load | Lighten the load. |
Causes and Troubleshooting for the Engine Not Being Started
| CAUSES | TROUBLESHOOTING |
| It is cold
Machine oil is viscous |
Fill machine oil into crankcase after warming-up. Fill machine oil into inlet pipe
Remove the connection belt from the machine Start the engine and stop it when it is heating, assemble the belt and then restart the engine. |
| Failure of fuel system.
Water mixed in the fuel |
Clean fuel tank, fuel filter and fuel pipe, then change the fuel. |
| The fuel get thickening and can’t flow easily | Use prescribed brand fuel |
| Air exists in fuel system | Emit the air, tighten each connect part to the fuel pipe |
| Injection fuel is little or the spray is not excellent | Check the position of governing handle or check and clean the fuel nozzle, change the nozzle if necessary. |
| Incomplete combustion | Mainly by ill spray Incorrect delivery angle
Leakage in gasket of cylinder head Deficiency in pressure of compression |
| Interrupted of diesel fuel | Lack of oil, should fill fuel into the fuel tank. If have obstruction or leakage in the fuel pipe and fuel filter, drain out them with the air. |
| Deficiency in pressure of compression; Loosen in the nut of cylinder head; Damage or leakage in the gasket of cylinder | Tighten the nut of cylinder head in the diagonal sequence; check the gasket of cylinder as per the standard requirement. When the engine with the new gasket is heating, tighten the nut of cylinder head again. |
| Big gap in the piston ring due to wear and tear | Change the piston ring |
| Leakage caused by each gap of piston ring lined in one direction | Make each gap of piston at angle of 120 |
| Serious stickiness or breakage in piston ring | Clean it by diesel fuel or change the piston ring. |
| Leakage in gas valves | Skive the gas valve, or send it to repair factory if the vestige is too deep. |
| Incorrect in valve clearance | Adjust the gap as specified. |
| The valve stem is clipped in the guide pipe | Disassemble the gas valve, clean the stem and guide pipe with diesel fuel. |
Causes and Troubleshooting for Deficient Power of Diesel Engine
| CAUSES | TROUBLESHOOTING |
| Malfunction of fuel system;
Parts obstruction in fuel filter and fuel pipe; Inadequate fuel supplying; |
Check the fuel switch, they should be opened fully.
Clean the fuel filter and fuel pipe. |
| Bad pressing of fuel pump | Check or change the damaged parts of fuel pump. |
| Malfunction of the fuel nozzle;
Incorrect injection pressure |
Adjust the injection pressure |
| Carbon deposit in the nozzle hole | Clean |
| Needle was bit | Clean or change |
| Loose fit between needle and needle body | Change |
| Obstruction in air filter | Remove, clean or change the filter core. |
| Not fast enough of engine speed | Check the speed of engine with the tachometer, and then readjust
the speed limit bolt. |
Causes and Troubleshooting for Exhaust with Black Smoke
| CAUSES | TROUBLESHOOTING |
| Overload | Lighten the load; change the matched machine if it does not
comply with the requirements. |
| Bad spray | Check injection pressure and spray condition and remedy;
change the nozzle if it was damaged. |
| Lack of air or leakage | Clean the air filter; check the cause of leakage and remedy. |
| Machine oil mixed in cylinder | Check the oil level, drain off the redundant engine oil |
| Piston ring is clipped, worn or lack of elasticity, hatch of each ring turned to the
same direction and make engine oil up |
Check and replace the piston ring, and cross hatch of each ring |
| Big gap between piston and cylinder | Remedy or change |
| Wear and tear of valve and guide | Change |
Causes and Troubleshooting for Exhaust with White Smoke
| CAUSES | TROUBLESHOOTING |
| Water mixed in diesel fuel | Clean the fuel tank and filter and change the diesel fuel. |
Diesel Generator Troubleshooting and Rectifying Malfunction
Causes and troubleshooting for the generator not being started
| CAUSES | TROUBLESHOOTING |
| Lack of diesel fuel | Add diesel fuel |
| Oil switch is not on the position of “ON” (start switch) | Turn oil switch handle to the position of “ON” |
| No or little spray from injection pump and nozzle | Disassemble the nozzle and adjust it on the test table |
| The governor handle is not on the position of “RUN” | Turn the governor handle to the position of “RUN” |
| Check the lubricating oil level | The standard of lubricating oil is between upper line “H” and bottom line “L” |
| Recoil starter is not swift and powerful enough | Start the engine according to “ Start Operation Procedure” |
| Dirty in the nozzle | Clean the nozzle |
| No electricity of storage battery | Charge up or change the storage battery |
Causes and troubleshooting for the generator not generating electricity
| CAUSE | TROUBLESHOOTING |
| Power switch is on the position of “OFF” | Turn the switch handle to the position of “ON” |
| Bad contact of the socket | Adjust the socket pins |
| Damage of capacitor | Change the capacitor |
Damage Cause and Remedy of Brushless Alternator
| Phenomena | Cause | Remedy |
|
Can not generate |
Switch is on the position of “OFF”. | Turn the switch to the position “ON”. |
| Worse connection of the plug or the control panel. | Adjust the contactor of the plug or the wires inside the control panel. | |
| Circuit break of the coil of the stator; or the capacitor overloads. | Check the stator at the point of the break; If it is the just reason that causes problem, change the stator; Or check the capacitor with the multimeter, if the needle does not move, change the capacitor. | |
| Short circuit of the rectifier. | Check the rectifier by the Multimeter as the following steps: connect the pens to each two of the four contactors of the rectifiers both in the clock-wise way and in the counter-clock-wise way; if you find that | |
| Connection between the coil of the rotor and the rectifier is wrong, which can not make the different magnetic poles (N/S). | Check the reel and the rectifier by the Multimeter. Kindly note the current way while connecting. The correct connecting diagram is just shown as the right one. | |
|
Low Voltage |
Low engine speed | Increase the engine speed. |
| Short-circuit of the rotor reels. | Change the rotor. | |
| Short-circuit of the capacitor or the stator. | Chang the stator. | |
|
Others |
The rectifier of the rotor got short circuit by the over-current. The voltage decreases. | Check the rectifier as per the above instruction. Replace a new one. |
| After loading, the PTO shaft skids. And the voltage decreases, the alternator overheats. | Disassemble the engine. Maintain the PTO shaft and the inside pole of the rotor until the conic degree reaches to the reasonable level. Then assemble the engine. | |
| Short-circuit of the rotor or the stator makes the alternator overheat. The voltage decreases. | Change the stator or the rotor. |
Damage Cause and Remedy of The Brushed Alternator
| Phenomena | Cause | Remedy |
|
Can not generate |
Switch is on the position of “OFF”. | Turn the switch to the position “ON”. |
| Worst connection of the plug or the control panel. | Adjust the contactor of the plug or the wires inside the control panel. | |
| The connection of the AVR contactor is bad or AVR burns. | Connect the contactor well or change AVR. | |
| The carbon brush wears out or its positive pole and its negative poles are connected
crossly. |
Change the carbon brush or make the wrong connection right. | |
| The second reel of the alternator has turnoff. | Check the reel by the Multimeter, change the stator if it needs. | |
| The rotor has turnoff. | Check the reel by the Multimeter, change the rotor if it needs. | |
|
Low Voltage |
Low engine speed | Increase the engine speed. |
| Short-circuit of the rotor reels. AVR burns. | Change AVR firstly. If the voltage is not high enough, change the rotor. | |
| Short-circuit of the capacitor or the stator. | Chang the stator. | |
| The sample voltage has short circuit. | Adjust the resistance of AVR. If the voltage remains, change the stator of the alternator | |
|
Others |
AVR burns after load. The voltage decreases, even disappear. | Change AVR. |
| After loading, the PTO shafts skids. And the voltage decreases, the alternator overheats. | Disassemble the engine.
Maintain the PTO shaft and the inside pole of the rotor until the conic degree reaches to the reasonable level. Then assemble the engine. |
|
| Short-circuit of the rotor or the stator makes the alternator overheat. The voltage decreases. | Change the stator or the rotor. |
Diesel Generator Inspection Checklist
| S.# | ITEM | OK | Remarks |
| 1 | Oil leaks (engine) | ||
| 2 | Radiator (water leaks, water sufficient) | ||
| 3 | Cooling Water Hoses | ||
| 4 | Exhaust System/spark arrestor | ||
| 5 | Electrical Control Panel | ||
| 6 | Electrical distribution board connections | ||
| 7 | GFCI/ELCB unit | ||
| 8 | Earth Bonding Connections | ||
| 9 | Machine Lifting Eye | ||
| 10 | Fire Extinguisher | ||
| 11 | Fuel lines (leaks) | ||
| 12 | Fuel Tank and Filler Cap | ||
| 13 | Sound dampers | ||
| 14 | Side screens in Position | ||
| 15 | Battery condition | ||
| 16 | Secondary containment(spill tray) | ||
| 17 | Emergency stop |
