Engine oil is the lifeblood of an engine, and oil changes are considered minor maintenance, the most basic type of service. Why change the oil? What should you pay attention to when using engine oil? Here comes the simplest guide to oil maintenance! Today, Kang Ge will use this illustrated article to tell Kang Fans about the role of engine oil and how to use it correctly.

How engine oil works

When the engine is running, the drive gear on the camshaft drives the transmission gear of the oil pump, causing the drive gear fixed to the drive gear shaft to rotate. This, in turn, drives the driven gear to rotate in the opposite direction, pumping oil from the oil chamber through the gear clearance and pump wall to the outlet chamber. As a result, a low-pressure zone is formed in the inlet chamber, creating suction that draws oil from the oil chamber housing into the inlet chamber. Due to the continuous rotation of the drive and driven gears, the oil is continuously pressurized and delivered to critical components.

A picture shows you the function of motor oil

Misconceptions about motor oil use

Misconception 1: If engine oil turns black, it needs to be replaced.  

Engine oil has a cleaning function, capable of removing carbon deposits and oxidation products from the engine's internal components and dissolving them. The black substances we observe in engine oil are the carbon deposits and oxidation byproducts from the engine's internal components. Therefore, regardless of how clear the engine oil may be, it will inevitably turn black after being used in the engine for a period of time. This is a normal result of the oil performing its cleaning function, so turning black is entirely normal and does not necessitate replacement.

Misconception 2: The thinner the oil, the better

High-end oils have lower viscosity, leading many users to believe that lower viscosity is always better. However, the choice of oil viscosity should still be based on the manual, as only the appropriate viscosity can achieve optimal performance. Additionally, the actual operating conditions of the engine must be considered. Too low or too high viscosity can respectively lead to inadequate lubrication or excessive operational resistance.

Misconception 3: Only top up oil, never change it

Motor oil has cleaning properties, but its performance degrades over time due to contamination and oxidation, and it is also consumed during use. If you only top up the oil without changing it, you can only compensate for the quantity deficiency, not the performance loss.

Misconception 4: Altering additives on your own

High-quality engine oil is a finished product with multiple engine protection functions, and its formulation already contains various additives, including anti-wear agents. The formulation of engine oil is carefully balanced to ensure the full utilization of its various properties. Adding other additives on your own not only fails to provide additional protection for the equipment but may also react with the chemical substances in the engine oil, leading to a decline in its overall performance.

Misconception 5: It is better to add more oil than less

The oil level should be maintained between the high and low marks on the dipstick. Excessive oil can seep into the combustion chamber through the gaps between the cylinder and piston, where it burns and forms carbon deposits. These deposits increase the engine's compression ratio, raising the likelihood of engine knocking. Additionally, excessive oil increases the stirring resistance of the crankshaft connecting rod, leading to increased fuel consumption. Furthermore, adding too much oil can increase internal engine pressure, potentially causing oil leaks from engine seals.

How to use motor oil correctly

1. Regularly check the oil level.

Specific steps:

(1) The equipment must be placed horizontally when checking the oil level.

Tips: 

To ensure accurate measurements, wait at least 15 minutes after the engine has stopped before checking the oil level. This allows the oil to flow back into the oil pan.

(2) The oil level should be maintained between the high and low markings on the dipstick.

Tips:

1) If the oil level is significantly above the “high mark,” it increases the stirring resistance of the crankshaft connecting rod, leading to increased fuel consumption.

2) If the oil level is below the “low mark,” it may result in insufficient lubrication, cleaning, and cooling capabilities, causing increased wear and tear. In severe cases, this can lead to major engine failures such as crankshaft seizure or bearing failure.

2. Regularly change the engine oil

(1) Selection of engine oil

Since engine oil has a significant impact on the performance and lifespan of the engine, it is essential to strictly follow the manufacturer's specifications when selecting engine oil of the same series, grade, and viscosity. If the manual is unavailable, the following methods can be used to select the appropriate engine oil specification.

• Select the corresponding series of engine oil based on the type of fuel used by the engine. According to the API (American Petroleum Institute) classification, diesel engines should use C-series oil (diesel engine oil specifications have evolved from the initial CA to the current highest grade CI-4).

• Select based on the SAE (Society of Automotive Engineers) standard viscosity values.

(2) Oil change cycle

Oil should not be changed simply because it has turned black, but rather according to the oil change standards.

(3) Oil change method and steps