為什么換完機(jī)油后發(fā)動(dòng)機(jī)的聲音更大了？

Why does the engine sound louder after changing the oil?

1.機(jī)油過量

1. Excessive engine oil

機(jī)油加注也是有標(biāo)準(zhǔn)的，并非是越多越好，如果機(jī)油加注量過多，對(duì)曲軸旋轉(zhuǎn)工作產(chǎn)生更大的阻力，從而影響動(dòng)力輸出，增加油耗。進(jìn)入燃燒室的機(jī)油量大大增加，使燃燒室內(nèi)積碳增多，增加了活塞運(yùn)動(dòng)阻力，使發(fā)動(dòng)機(jī)功率下降。同時(shí)也會(huì)造成燃燒室空燃比發(fā)生變化，增加爆震的幾率，噪音也會(huì)隨之加大。

There is also a standard for oil filling, not the more the better. If the oil filling is too much, it will produce greater resistance to the rotation of the crankshaft, thus affecting the power output and increasing fuel consumption. The amount of oil entering the combustion chamber is greatly increased, which increases the carbon deposition in the combustion chamber, increases the piston movement resistance and reduces the engine power. At the same time, it will also cause the air-fuel ratio of the combustion chamber to change, increase the probability of detonation and increase the noise.

2.中度積碳

2. Moderate carbon deposition

老機(jī)油越用越稀，積碳越來越多。機(jī)油稀了容易竄機(jī)油，造成積碳越來越多。當(dāng)換上新機(jī)油時(shí)，發(fā)動(dòng)機(jī)不能適應(yīng)機(jī)油粘度，可能會(huì)拉高轉(zhuǎn)速，進(jìn)而造成發(fā)動(dòng)機(jī)噪音大。建議用高標(biāo)號(hào)汽油開高轉(zhuǎn)速，建議保持開2500轉(zhuǎn)以上開一箱高標(biāo)號(hào)油應(yīng)該就有改善，當(dāng)然也可以進(jìn)行預(yù)防性清洗。

The old engine oil is thinner and thinner, and carbon deposits are more and more. When the engine oil is thin, it is easy to channelle the engine oil, resulting in more and more carbon deposition. When the engine is replaced with new oil, the engine cannot adapt to the oil viscosity, which may increase the speed and cause loud engine noise. It is recommended to use high-grade gasoline to drive at high speed. It is recommended to keep driving more than 2500 rpm. Opening a box of high-grade oil should be improved. Of course, preventive cleaning can also be carried out.

3.機(jī)油粘度要適合

3. The oil viscosity shall be suitable

不同等級(jí)的機(jī)油有著不同的特性，其低溫啟動(dòng)性和高溫的抗磨、附著性也有著不同的表現(xiàn)。機(jī)油的黏度與溫度呈反比的關(guān)系，當(dāng)發(fā)動(dòng)機(jī)冷態(tài)時(shí)，機(jī)油黏度較高，若選用的機(jī)油較稠，便會(huì)給啟動(dòng)馬達(dá)、電瓶等增加額外的損耗。但若機(jī)油過稀，在高溫工作下則難以形成足夠的保護(hù)膜而引起潤滑不足，導(dǎo)致機(jī)件加大磨損。如果車輛手冊(cè)建議5W-30，而車主要用5W-40的那發(fā)動(dòng)機(jī)噪音變大，那么車主就需要注意了。建議選機(jī)油建議是車輛手冊(cè)推薦的標(biāo)號(hào)。

Different grades of engine oils have different characteristics, and their low-temperature start-up and high-temperature anti-wear and adhesion also have different performances. The viscosity of the engine oil is inversely proportional to the temperature. When the engine is cold, the viscosity of the engine oil is high. If the selected engine oil is thick, additional losses will be added to the starting motor and battery. However, if the engine oil is too thin, it is difficult to form sufficient protective film under high temperature operation, resulting in insufficient lubrication and increased wear of parts. If the vehicle manual recommends 5W-30 and the vehicle mainly uses 5W-40, the engine noise becomes louder, then the owner needs to pay attention. The recommended engine oil is the grade recommended in the vehicle manual.

4.機(jī)油混加

4. Oil mixing

這種情況也比較常見，由于不同品牌用的技術(shù)配方不同，可能會(huì)產(chǎn)生不良化學(xué)反應(yīng)，改變其本身自有的特性，從而對(duì)發(fā)動(dòng)機(jī)造成磨損，噪音增加。建議車友們建議不要混加機(jī)油，盡量使用同一品牌的機(jī)油。如遇特殊情況更換不同品牌機(jī)油，建議使用同標(biāo)號(hào)機(jī)油。

This situation is also common. Due to different technical formulas used by different brands, adverse chemical reactions may occur and their own characteristics may be changed, resulting in engine wear and increased noise. It is recommended that motorists do not mix engine oil and try to use the same brand of engine oil. In case of special circumstances, it is recommended to replace oil of different brands with oil of the same grade.

5.遇到假機(jī)油

5. False engine oil

這種情況也是很有可能出現(xiàn)的，由于新手司機(jī)在給自己的愛車做保養(yǎng)時(shí)，加入了劣質(zhì)的機(jī)油。由于“假”機(jī)油它的抗磨、清潔、潤滑保護(hù)等性能都非常差，導(dǎo)致發(fā)動(dòng)機(jī)壓力過大，從而磨損加劇、噪聲加大。作為消費(fèi)者，對(duì)相關(guān)的防偽知識(shí)要知道一些，不能只道聽途說，要懂得如何辨別機(jī)油的真?zhèn)巍?/p>

This situation is also likely to occur, because novice drivers add inferior engine oil when maintaining their car. Due to the poor anti-wear, cleaning and lubrication protection of "fake" engine oil, the engine pressure is too high, resulting in increased wear and noise. As consumers, they should know some relevant anti-counterfeiting knowledge, not just hearsay, but how to distinguish the authenticity of engine oil.

6.冷車聲音大正常

6. The sound of cold car is loud and normal

冷車狀態(tài)機(jī)油大部分都回流到油底殼，這時(shí)候發(fā)動(dòng)機(jī)內(nèi)部器件缺少潤滑，冷車啟動(dòng)的時(shí)候發(fā)動(dòng)機(jī)溫度還會(huì)變低，機(jī)油的潤滑性能也達(dá)不到好的狀態(tài)，加上發(fā)動(dòng)機(jī)預(yù)熱轉(zhuǎn)速的原因會(huì)造成噪音偏大，但熱車后噪音轉(zhuǎn)速又會(huì)降下來了，這個(gè)是正常情況。如果熱車后沒有恢復(fù)正常，建議大家去檢查一下。

When the engine is cold, most of the engine oil flows back to the oil pan. At this time, the internal components of the engine are lack of lubrication. When the engine is cold, the engine temperature will become lower, and the lubrication performance of the engine oil can not reach a good state. In addition, due to the preheating speed of the engine, the noise will be too high, but the noise speed will drop again after the hot car. This is a normal situation. If it doesn't return to normal after hot driving, I suggest you check it.

7.心理作用

7. Psychological function

這個(gè)應(yīng)該是占大多數(shù)，人的聽力在不同的環(huán)境是有誤差的，單憑耳朵是不能判定聲音變大的，建議用分貝儀測(cè)量。從油品粘度的技術(shù)角度分析，5W-20、5W-30的機(jī)油在市區(qū)行駛中噪音會(huì)稍微大些，在高速正常行駛，噪音會(huì)稍小些。5W-40、5W-50的油品在市區(qū)行駛中噪音會(huì)稍小些，上了高速正常行駛，噪音會(huì)稍大些。

This should account for the majority. People's hearing has errors in differe