——There is abnormal noise in the diesel engine?

An article teaches you how to troubleshoot the causes of diesel engine failures yourself!

Reason 1: The fuel supply advance angle is too large, and there is rhythmic metal percussion in the cylinder

Troubleshooting method: adjust the fuel supply advance angle

Reason 2: The fuel injection nozzle drips oil and the needle valve is seized, causing a sudden "click, click, click" sound

Troubleshooting method: clean, repair, and replace the needle valve assembly

Reason 3: The valve clearance is too large, and there is a rhythmic and clean knocking sound

Troubleshooting method: adjust valve clearance

Reason 4: The piston hits the valve, and there is a heavy and evenly rhythmic knocking sound (lightly place your hand on the cylinder head cover nut to feel the vibration of the piston hitting)

Troubleshooting method: appropriately increase the air valve gap, correct the gap of the connecting rod bearing, or replace the connecting rod bushing

Reason 5: The piston hits the bottom of the cylinder valve, and a heavy and powerful impact can be heard

Troubleshooting method: optional cylinder head gasket

Reason 6: The valve spring is broken, the valve push rod is bent, and the valve lifter is worn, causing the valve engine to make a slight knocking sound

Troubleshooting method: replace the spring, push rod or tappet, etc. and adjust the valve clearance

Reason 7: The abnormal noise caused by the excessive clearance between the piston and the cylinder liner, which is reduced as the diesel engine heats up

Troubleshooting method: change cylinder liner and piston according to wear

Reason 8: When the connecting rod bearing clearance is too large, when the speed drops suddenly, a heavy and powerful impact can be heard

Troubleshooting method: replace the connecting rod bearing

Reason 9: The gap between the connecting rod bushing and the piston pin is too large, the sound is slightly sharp, and it is particularly clear when idling

Troubleshooting method: replace the connecting rod bearing

Reason 10: When the axial clearance of the crankshaft thrust plate is too large, the crankshaft can be heard moving forward and backward at idle speed.

Troubleshooting method: replace the crankshaft thrust plate