What does it mean that "engine valve adjustment can't go into two rows"?

In the valve adjustment of a 4-cylinder engine, it means that the piston of 1 cylinder is at the top dead center. At this time, the clearance between the two valves of 1 cylinder can be adjusted by adjusting the valves, which is called "double". At the same time, cylinder 2 can adjust the exhaust valve clearance, which is called "exhaust".

If cylinder 3 cannot be adjusted, it is called "No". Four cylinders can adjust the intake valve, which is called "intake". This constitutes the formula of "double row does not enter".

Valve, the external breathing hole of the trachea system of insects or other arthropods, and the ventilation hole of the lung sac of arachnids. The Fortieth Story of Heroes of Children: "Only this sentence, An Gongzi felt that the top door slammed and his heart couldn't stop jumping up and down. If the valve hadn't resisted, he almost didn't jump out, and the color on his face suddenly changed. " It refers to the throat.

Automobile valve, also known as throttle, is responsible for injecting fuel into the engine and discharging exhaust gas. In traditional engines, each cylinder has only one intake valve and one exhaust valve. This design has the advantages of simple structure, low cost, convenient maintenance and good low speed performance. The disadvantage is that the power is difficult to improve, especially at high speed, the inflation efficiency is low and the performance is weak.