Why is the engine so noisy? How to solve it?
1. First, let’s talk about the common problem of loud valve sound. What is the reason for the loud valve sound? How to solve?
a. If it is a hydraulic lift-type cylinder head, if the valve sound is loud, it may be that the engine oiling is not good due to insufficient oil pressure or lack of oil. In this case, the valve lifter is not well lubricated and a rattling noise will occur!
It may also be that the hydraulic lifter is damaged and the sound occurs due to excessive clearance caused by its own failure!
How to solve this situation? First check whether there is a lack of engine oil, then test whether the oil pressure is normal, and finally disassemble the valve cover and check whether there is any problem with each hydraulic lifter!
b. There is also a valve that is gasketed or adjustable.
If this kind of rattling sound occurs, you must first rule out whether it is caused by poor oiling caused by insufficient engine oil!
Then consider the gap issue! The gasket is more difficult to adjust. The adjustable valve only needs to be adjusted to the normal range!
2. The belt makes abnormal noise! This includes the squeaking of the belt itself, as well as the sounds made by the compressor, tensioner pulley, generator, booster pump, water pump, drop pulley, etc.!
For example, if the tensioner bearing makes abnormal noise, it may be that the bearing is broken or lacks oil! If the water pump bearing is broken, is there a sound of iron touching iron?
3. If there is a problem with the clutch or gearbox of a manual transmission car, you may also hear loud engine noise!
4. Another thing is the sound caused by engine resonance!
Generally, this sound is more obvious inside the cab and almost impossible to hear outside!
This situation is usually caused by a problem with the engine floor mats. The engine noise is directly transmitted to the cab without being buffered by the floor mats! For this, you need to check the floor mats directly, and then see if any parts on the engine are in direct contact with the car shell!
5. The engine knocks on the cylinder and the engine bearing makes a very crisp sound!
This is usually caused by insufficient engine oil lubrication. If this happens, the engine usually needs to be overhauled!