What are the effects of high and low oil viscosity on car engines?
1 Answers
Oil viscosity has the following effects on car engines: 1. If the engine oil viscosity is too high, the resistance during engine operation increases, leading to higher fuel consumption, and the engine speed rises relatively slowly after pressing the accelerator. 2. If the engine oil viscosity is too low, it cannot form a stable oil film on the surface of various components during engine operation, resulting in poor lubrication. Below is extended information on the effects of oil viscosity on engines: 1. If the oil viscosity is too high, the oil film becomes too thick, increasing resistance due to oil viscosity and causing adverse effects. The car becomes harder to start and accelerates sluggishly. Engine power output decreases, and cooling efficiency worsens. The car consumes more fuel, leading to wastage. Due to poor oil fluidity, it cannot quickly reach the cylinders, increasing wear during startup. 2. If the oil viscosity is too low, it also adversely affects the engine. The oil film thickness is insufficient, and the oil film strength is weak, making it easily disrupted. It is difficult to form a sufficiently thick oil film on high-temperature, high-pressure friction surfaces, preventing normal lubrication and causing excessive engine wear. The sealing effect is poor, and low oil viscosity leads to inadequate piston ring sealing, directly causing combustion chamber blow-by and oil burning. Engine noise increases.
