How to adjust the valve clearance of cylinder 6

Due to the different arrangement of various types of valves, the adjustment order has also changed. The following methods are for reference only, please adjust according to the valve model of your car:

Check and adjust the valve clearance when the valve is completely closed and the valve tappet is lowered to the lowest position. Generally, at the end of the cylinder compression stroke, the intake valve and the exhaust valve are adjusted at the same time. For a six-cylinder engine, there are two adjustment methods:

Cylinder-by-cylinder adjustment is a cylinder-by-cylinder adjustment. According to the ignition sequence of the cylinder, the intake valve and exhaust valve of the cylinder are adjusted at the end of the compression stroke and when the piston reaches the top dead center. This cylinder-by-cylinder adjustment ensures quality. The adjustment method is:

Loosen the lock nut, insert a feeler gauge with the specified clearance between the end of the valve stem and the rocker arm (overhead valve), pull the feeler gauge back and forth, and turn the adjusting screw (internal thread) until the clearance is appropriate and there is slight resistance.

After the valve clearance is adjusted, tighten the lock nut reliably.

Review, if the gap changes, it needs to be readjusted.

According to the calculation of engine working cycle, ignition sequence, crankshaft supporting function and actual opening and closing angles of valves, the twice adjustment method can adjust not only two valves of cylinder 1 (or) 6 at the end of compression of cylinder 1 (or) 6, but also one valve of other cylinders. In this way, the valve of a six-cylinder engine can be completely adjusted only by turning the crankshaft twice, which is simpler and easier than cylinder-by-cylinder adjustment.

Turn the crankshaft so that the timing mark -I-J- on the flywheel is aligned with the scribing line on the inspection hole of the flywheel housing. ?

At this time, if the two valves of the sixth cylinder are slightly opened at the same time, the compression stroke of 1 cylinder ends, and the valve clearances of 1, 2, 3, 5, 7 and 9 cylinders can be checked and adjusted.

After adjusting the above six valves, rotate the crankshaft again so that the marks on the flywheel are aligned with the scribed lines of the inspection holes of the flywheel housing again. At this time, the sixth cylinder is at the end of the compression stroke, and the valve clearances of the fourth, sixth, eighth, 10,1,12 can be checked and adjusted.

Valve clearance:

When the engine is working, the valve will expand due to the increase of temperature. If there is no gap between the valve and its transmission parts in the cold state or the gap is too small, then the thermal expansion of the valve and its transmission parts in the hot state will inevitably lead to the untidy closing of the valve, resulting in air leakage in the compression stroke and power stroke of the engine, thus reducing the power and even making it difficult to start. In order to eliminate this phenomenon, when the engine is assembled in cold state, a certain gap is usually left in the valve and its transmission mechanism to compensate for the expansion of the valve after heating. This clearance is called valve clearance.

References:

Baidu encyclopedia-valve clearance