What to Do When a Car Brake Pump Leaks Air?

Can Cars Use Methanol Gasoline?

Gasoline vehicles can only use methanol under one condition: the car must be a dedicated methanol vehicle designed to use methanol as fuel. This is because methanol vehicles are equipped with specialized engines and devices that allow for the safe use of methanol. Other vehicles should not use methanol. Hazards of Methanol Gasoline to Vehicles: Methanol typically contains acidic substances during production, and its inherent hygroscopic nature means it retains small amounts of water during storage. Additionally, oxidation by air or bacterial fermentation can produce small quantities of organic acids. Furthermore, the formaldehyde and formic acid generated after methanol combustion can cause severe corrosion and wear to the engine. Research by Ford Motor Company in the U.S. found that using methanol gasoline increases the iron content in engine lubricating oil by 5.2 times compared to unleaded gasoline. The primary wear and corrosion occur on piston rings and cylinder walls, mainly due to the erosion of metal surfaces by methanol and its combustion byproducts, such as formic acid, formed through intermediate free radical reactions. Additionally, methanol's high latent heat of evaporation can lead to poor vaporization, causing it to flow into cylinder walls, wash away the lubricating oil film, dilute the oil, and result in severe emulsification, leading to friction wear on engine components.

2

Share

Can You Mix Different Engine Oils in a Car?

It is not advisable to mix different engine oils in a car. The reasons why engine oils should not be mixed include reduced performance when new and old oils are mixed, and the formation of turbidity when different oils are combined. Below are the detailed explanations: Mixing new and old oils reduces performance: New and old engine oils should not be mixed. Old oil contains a large amount of oxidative substances. When new oil is mixed with old oil, the oxidation rate of the new oil increases, thereby reducing its effectiveness and service life. Tests have shown that when the old oil in a diesel engine is completely replaced with new oil, the oil's service life can reach up to 1,500 hours. However, if half of the new oil is mixed with half of the old oil, the service life of the oil is reduced to only 200 hours, significantly shortening its usability. Mixing different oils causes turbidity: Engine oils of different brands and grades should not be mixed. Since the chemical additives in oils of different brands and grades vary, these additives can sometimes react with each other, reducing lubrication effectiveness and producing acidic or alkaline compounds that accelerate the corrosion of engine components. Most modern engine oils use sulfonates as dispersant detergents, while some oils use salicylates instead. Salicylates are incompatible with the sulfonates used in other lubricants. If these two types of lubricants are mixed, phenomena such as layering, turbidity, and deterioration of cleaning ability may occur.

11

4

Share

Is a tire pressure of 2.8 normal in summer?

Summer tire pressure of 2.8 is not normal. According to the provisions and requirements of the international GBT2978-2008 standard, the standard tire pressure for standard tires is 2.4-2.5bar. A pressure of 2.8bar exceeds the maximum value of the standard tire pressure, so it is not normal. Generally, the lower limit of the standard tire pressure for car tires is sufficient. For example, the lower limit for standard tires is 2.4bar. If the car is often parked outdoors, the tire pressure can generally be about 0.1bar lower than the standard to avoid tire blowouts due to high temperatures. Hazards of excessive tire pressure: The friction and adhesion of the tire will decrease, affecting braking performance; It can cause steering wheel vibration and deviation, reducing driving comfort; It accelerates the local wear of the tread pattern in the center of the tire, reducing the tire's lifespan; The vibration of the car body increases, indirectly affecting the lifespan of other components; It causes excessive stretching and deformation of the tire cords, reducing the elasticity of the tire body and increasing the load the car bears while driving; Puncture resistance decreases. When encountering sharp objects like nails or glass on the road, they can easily penetrate the tire, and the impact can cause internal cracks and explosions, leading to a blowout.

14

2

Share

What is the principle of car steering?

The principle of car steering mainly involves the steering wheel driving the steering gear, which in turn activates the rack and pinion steering mechanism. This causes the front tie rod to swing left and right, changing the angle of the front wheels to achieve the steering effect. The car steering system is used to maintain or change the direction of the vehicle's movement, whether moving forward or backward. The car steering system is crucial for driving safety, which is why its components are referred to as safety-critical parts. Both the steering system and the braking system are essential safety systems that must be given high priority in vehicles. Structure of car steering mechanisms: In terms of widespread usage, there are four main types of steering mechanisms: worm and peg type (WP), worm and roller type (WR), recirculating ball type (BS), and rack and pinion type (RP). These four types of steering mechanisms have been widely used in automobiles. Among them, the recirculating ball steering mechanism and the rack and pinion steering mechanism have become the two primary steering systems in modern vehicles worldwide. Meanwhile, the worm-type steering mechanisms are gradually being phased out or retaining a minor role. Due to its various advantages, the rack and pinion steering mechanism has seen rapid development in small vehicles (including passenger cars, light trucks, and multi-purpose vehicles). On the other hand, larger vehicles primarily use the recirculating ball steering mechanism as their main structure.

18

4

Share

What is the heating symbol for a sedan?

The heating symbol in a car is typically a rotary knob. To increase the interior temperature, turn on the air conditioning and rotate the knob to the red zone. The heating switch symbol usually has red and blue markings on both sides, with the cold air setting on the left and the heating setting on the right. Turning the knob to the left lowers the car's temperature, while turning it to the right raises it. Some models also feature an automatic air conditioning system; pressing the AUTO button will allow the system to adjust the temperature automatically based on the interior conditions. Before turning on the heating, it's necessary to wait for the engine coolant temperature to rise. When the car is cold-started, the coolant temperature is at 0 degrees. Only after driving for some time will the temperature noticeably increase. Once the coolant temperature reaches around 90 degrees, the car's heating system will become effective. It's important to note that the A/C button should be turned off when using the heating. This is because the heating system utilizes the heat generated by the engine. Activating the air conditioning compressor can reduce the heating efficiency and increase fuel consumption. Driving with the heating on can lead to fatigue. It's advisable to adjust the air vents to avoid blowing directly at the head for extended periods, as this can cause drowsiness and affect driving safety. Periodically opening the windows to allow fresh air circulation is also recommended to maintain a comfortable and safe driving environment.

1

2

Share

How many points are deducted for driving or parking in violation of regulations?

When driving through an intersection without following the prescribed driving or parking rules, 2 points will be deducted. Below is a detailed introduction about vehicle violations: 1. Overview: Vehicle violations refer to motor vehicles violating the Road Traffic Safety Law and traffic management regulations. Penalties for vehicle violations include warnings, fines (vehicle impoundment), temporary suspension of driver's license, revocation of driver's license, cancellation of driver's license, administrative detention, and criminal liability for acts constituting a crime. 2. Basis for Penalties: According to the 'Road Traffic Safety Law of the People's Republic of China,' public security traffic management departments and their traffic police should promptly correct road traffic safety violations. Penalties for road traffic safety violations should be imposed based on facts and relevant provisions of this law.

19

3

Share

What to Do When a Car Brake Pump Leaks Air?

Can Cars Use Methanol Gasoline?

Can You Mix Different Engine Oils in a Car?

Is a tire pressure of 2.8 normal in summer?

What is the principle of car steering?

What is the heating symbol for a sedan?

How many points are deducted for driving or parking in violation of regulations?

What Are the Types of Traffic Signals?

What are the differences between the 7th and 7.5 generation Golf?

How Often Can You Take the Subject 2 Test?

What is the difference between deducting 12 points and 23 points on a driver's license?