How to adjust the valve clearance of automobile?

The adjustment method of automobile valve clearance is as follows: 1. Turn the crankshaft so that the pulley mark is aligned with the score line, which means that the compression stroke of one cylinder or four cylinders is over. If it is at the end of the compression stroke of a cylinder, the valve clearances of 1, No.2, No.4 and No.6 can be adjusted from the front end of the engine; 2. Insert a thickness gauge with a specified thickness between the valve foot and the rocker arm and pull it back and forth. If you feel slight resistance, it is appropriate, otherwise it will be adjusted; 3. When adjusting, loosen the lock nut, turn the adjusting screw, insert the thickness gauge into the gap and pull it back and forth. If you feel a little resistance, it means that the gap is appropriate, fix the adjusting screw and check it again at last. If the gap changes, it needs to be readjusted; 4. After completing the above valve adjustment, rotate the crankshaft again, so that the marks on the flywheel are aligned with the scribed lines on the window of the flywheel housing again, and then the four cylinders are at the end of the compression stroke. Counting forward from the fourth cylinder, the clearances of 1, 2, 4 and 6 valves can be adjusted.