Different Abnormal Noises of 800KW Diesel Generator

Why does 800kW diesel power generator has different abnormal noises? Today, Dingbo power will answer for you!

A. Causes of general abnormal noise of 800kW diesel generator.

1. When you hear the abnormal sound during the operation of 800KW diesel generator, you should first determine where the sound comes from, such as the valve chamber, the inside of the engine body, the front cover plate, the joint between generator and diesel engine or in the cylinder. When the position is determined, it should be judged according to the working principle of the diesel engine.

2. When the abnormal sound is heard inside the engine body, stop the machine quickly, open the side cover plate of the diesel engine body, and push the middle position of the connecting rod by hand. If the sound is on the upper part of the connecting rod, it can be concluded that the copper sleeve of the piston and connecting rod has failed. If the noise is found at the lower part of the connecting rod during shaking, it can be concluded that the gap between the connecting rod pad and the journal is too large or the crankshaft itself is faulty.

3. When the abnormal sound is heard on the upper part of the engine body or in the valve chamber, it can be considered that the valve clearance is not adjusted properly, the valve spring is broken, the rocker arm seat is loose, or the valve push rod is not placed in the center of the tappet.

4. When an abnormal sound of diesel genset is heard at the front cover plate of the diesel engine, it can generally be considered that the clearance of various gears is too large, the fastening nuts of gears are loose, or some gears have gear beating fault.

5. When the abnormal sound is at the joint of diesel engine and generator, it can be considered that the internal interface rubber ring of diesel engine and generator is faulty.

6. When the abnormal sound comes from the inside of the cylinder, it can be concluded that the oil supply advance angle is improperly adjusted or the wear clearance between the piston and the cylinder liner increases.

7. When the sound of rotation inside the generator is heard after the diesel engine stops, it can be considered that the internal bearings or individual pins of the generator are loose.

B. Abnormal sound at cylinder, piston and piston ring. The sound of collision with the cylinder head occurs between the cylinder and the cylinder head when the engine is running at high speed. The continuous and crisp "Dangdang" metal knocking sound is solid and powerful, and the cylinder head is accompanied by some vibration.

a. The crankshaft bearing, connecting rod needle roller bearing or bearing and piston pin hole of 800KW diesel generator are seriously worn and loose. At the moment of piston up and down stroke speed, the piston crown will collide with the valve cover.

b. The size fit between the valve stem and the valve guide is not good, there is stagnation after the metal is heated and expanded, or the material meets the requirements, and the expansion coefficient is too large.

c. In case of other reasons, repair or replace relevant unqualified accessories.

Abnormal noise of valve stem end face and tappet adjusting bolt. When preheating for 3 ~ 5 minutes, the normal sound of lubricating oil will also decrease and disappear. The thickness of gasket is different! It should be judged from the position of the sound, the size and sharpness of the sound, the temperature, the load, the speed of rotation and so on, so as to accurately grasp the fault. 

C. The piston of 800KW diesel generator knocks.

(1) A continuous metal impact sound is heard on the upper part of the cylinder block.

(2) The piston is not elliptical, the connecting rod is bent and twisted, and the piston pin fits too tightly with the bushing or the connecting rod bearing fits too tightly with the Journal (often in the initial use stage after repair).

(3) If the sound disappears after the oil supply time is adjusted late, it means that the ignition or oil supply time is too early.

(3) Stop one cylinder and the sound has no obvious change; When two adjacent cylinders stop working at the same time, the sound will obviously decrease or disappear. Therefore, it is often mistaken for the sound of other parts.