Causes of abnormal noise in automobile generators from Pacific Automotive Network: 1. Generator V-belt slips 2. Generator bearings damaged 3. Rotor and stator collide forward; fan blades and front cover collision.
Metal friction noise is mainly caused by the damage of the bearing, or the friction noise of the bearing sleeve and housing; Vibration noise is caused by bearing aging, a loose, unbalanced foundation. Improper rotor and connecting shaft. Poor coordination, crankcase cracking, etc. ; buzzing, general overload, two elements, short circuit between turns, etc.
If it is a variable frequency motor, the frequency may be too high and the mechanical resonance point cannot be avoided. If there is no frequency converter, you must first determine whether the abnormal noise comes from the motor or fromu mechanical noise caused by the motor. Abnormal noise in the engine can be caused by a broken fan and severe bearing wear due to lack of oil. If the motor rotor shaft does not rotate but the motor makes abnormal noise, then it is sure that the rotor shaft and motor are damaged. The rotor windings (cast aluminum squirrel rotor) are loose.
To distinguish electromagnetic noise, mechanical noise or ventilation noise, the step-by-step operation method is generally used to distinguish, that is, disconnect a certain moving part to analyze the source of noise, for example. the noise generated by disconnecting the fan is electromagnetic noise or mechanical noise, then turn off the power supply, if the noise persists at the end, it can be determined as mechanical noise.
(Images/Text/Photos: Pacific Automotive Network Q&A)
The abnormal noise of the engine Can we say that this is a relatively common engine? Sometimes after changing the engine oil, or to be precise after changing the high viscosity engine oil, you can clearly hear the clicking sound of the engine. This is mainly due to the increase in internal resistance due to high viscosity, and. In general, this is also harmful to the engine. What is the impact of the engine?
But there is a problem with the hydraulic lifter, and it often clicks. The application of hydraulic lifters is to automatically eliminate valve clearance and reduce engine noise. However, once the hydraulic lifter fails, the engine will make a more serious "popping" noise.
Sharp knocking noises:
So-called sharp knocking noises, such as knocking triangles or knocking, are mainly caused by engine knocking or the phenomenon ofknocking of the cylinders. Engine knocking is a common occurrence, which is not necessarily a fault. This can also indicate that the engine is in poor condition, but cylinder knocking is mainly caused by a fault. Possible reasons for engine knocking are usually: advanced ignition angle, premature ignition causes abnormal pressure on the piston and causes the cylinder to knock. At this time, the ignition angle needs to be adjusted or deformation of the piston rod; cylinder deformation; piston and cylinder block. The gap is too big; Low-quality engine oil prevents parts from forming a protective lubricating oil film. Carbon or sludge deposits inside the engine are extremely serious, etc.
We are more familiar with engine knock. If the ignition angle is advanced or the engine compression is relatively high and the octane rating of the fuel addedis too low, engine knocking will easily occur. Whether it is knocking or knocking of cylinders, in addition to abnormal impact noises, they are often accompanied by engine vibrations.
Engine? Sizzle? Abnormal noise:
Actually, it is better to know the cause of this kind of abnormal engine noise. Nowadays, the abnormal "sizzling" noise is mainly caused by the aging of the belt assemblies of the engine, or the belt is too loose due to problems with the tensioner pulley, resulting in friction, abnormal noise, belt slippage, etc. If there is a similar abnormal "sizzling" sound, look for major belt and tensioner assemblies inside the engine, such as engine timing belts, generator belts, water pump belts, etc. circulation, air conditioning belts, booster pump belts, etc.
(Photo/Text/Photo: Shi Lili) @2019