The engine is the heart of an excavator. Once a failure occurs, it is difficult to continue using it. If the fault is dealt with in time, it may also cause engine damage. The engine is a very expensive component and should be carefully maintained. Today, I will tell you three common troubleshooting methods.

1, the clutch pedal is difficult to start.

The excavator is equipped with Mitsubishi S6D11115 diesel engine. When the clutch pedal is lowered, the diesel engine is difficult to start and the heat engine does not start. At this point, if you turn the crankshaft by hand, you will find it difficult to turn the crankshaft. This only happens when the clutch pedal is released.

Check the following: When the VOLVO excavator diesel engine is running, the clutch pedal is pressed, and the clutch will produce continuous noise. When the diesel engine is running at idle, as long as the engine presses the clutch pedal, the engine will immediately stop and preliminarily judge the clutch failure.

When the diesel engine is stationary, check the vehicle. When the clutch pedal is depressed, the clutch can rotate freely from the moving disc. Other parts are not damaged or abnormal, but the bearing cannot rotate.

In order to find out the cause of the failure, we decided to remove the clutch, but when removing the transmission, we unexpectedly found that the inner ring and bracket of the separation bearing were severely corroded and locked. After replacing the new separation bearing, the machine was re-tested and the fault disappeared.

2, can not start the diesel engine after overhaul.

An excavator equipped with an Isuzu 6b115 diesel engine was unable to start after a major overhaul. Although the diesel engine was very fast when it was forced to start, there was still no sign of fire.

The fuel system was checked and no blockage or leakage was found. Every cylinder pump and every injector has good fuel injection. The diesel cylinder pressure is normal, there is no problem with the timing of fuel supply. Since then, I suspected that the valve clearance was improperly adjusted and decided to readjust the valve clearance. Remove the high-pressure tubing and rotate the diesel engine forward to accurately adjust the valve clearance. When the oil flows out of the high-pressure tubing joint of the injection pump cylinder, it is found that the diesel cylinder is not at the top dead center of compression, and the six cylinders are at the top dead center of compression.

When the diesel engine rotates clockwise, the working sequence of the fuel injection pump is -; When the diesel engine rotates counterclockwise, the working order is normal. This is the opposite of the working order of diesel engines and fuel injection pumps.

Remove the fuel injection pump and check it carefully. It is found that the camshaft of the injection pump is installed upside down. After the camshaft is installed upside down, the diesel engine will have special faults, the working order is chaotic, and it cannot be started. Reinstall the camshaft in the correct way and then try to eliminate the fault again.

3, diesel engine after idle jitter overhaul.

VOLVO excavator diesel engine jitter seriously when running at idle after overhaul. According to the analysis, the newly built diesel engine may not be suitable for the mating clearance at a certain location during the assembly process. Therefore, the disassembly of the diesel engine should be fully checked.

Check the crankshaft's main journal and spindle. Connecting journal and connecting bearing. Piston skirt and cylinder wall. Clearance between piston and piston ring. No problems were found. During the process of removing the piston and connecting rod, it was found that the clearance between the small head bushing of the connecting rod and the cylinder piston pin was too small. The connecting rod bushings and piston pins can be rotated flexibly only after an overhaul of a 0.01mm diesel engine. However, because the clearance between the connecting rod bushing and the cylinder piston pin is too small, it is difficult to rotate the connecting rod, resulting in unbalanced crankshaft rotation and jitter, especially at idle. Repair the small head bushing of the cylinder connecting rod with a scraper. When servicing, try to match the piston pin until the clearance between the two meets the requirements. Then assemble the tester to eliminate the diesel engine idle jitter fault.

The above introduces three common troubleshooting methods of VOLVO excavator diesel engine, hoping to help you solve the excavator fault!