How to adjust the valve clearance of four-cylinder diesel engine?

1. First, open the valve cover and find a suitable preparation tool to turn the engine (manually turn the engine). Generally, there are valve clearance standards on the engine nameplate, such as: intake valve clearance: 0.25mm, exhaust valve clearance: 0.50 mm. Get a feeler gauge (also called thickness gauge) and find two engines corresponding to you, an intake valve and an exhaust valve;

2. Confirm the position of the engine valve. Failure to find a suitable valve will lead to valve clearance error. In general, the first adjustment can't find which is the intake valve and which is the exhaust valve. It's time to look at the exhaust pipe. For example, a cylinder has two valves. At this time, which valve of a cylinder is facing the seven manifolds of a cylinder, this is the exhaust valve, and the other is naturally the intake valve.

3. We adopt a simple and effective "cylinder by cylinder" adjustment method, that is, one cylinder by cylinder adjustment method. That is to say, when we want to adjust a cylinder, we turn the cylinder to the top dead center position, at which time the valve is in a free state, and both the intake valve and the exhaust valve can be adjusted. ? 4. We manually use the rotary tool to rotate the engine to the top dead center of the first cylinder, and check the valve during the rotation. When there is a gap between the intake valve and the exhaust valve (when the gap is maximum, it almost reaches the top dead center of the first cylinder). ) At this time, you can adjust the valve clearance of the first cylinder, loosen the lock nut of the intake valve of the first cylinder, put a suitable feeler between the valve and the rocker arm, and lock the nut after the feeler clearance is adjusted. Adjust the other two or three cylinders in the same way, and just adjust them three times. Check the adjustment method

1, cylinder by cylinder adjustment method. First, find the compression end point of a cylinder, adjust the gap between the intake valve and the exhaust valve of the cylinder, and then crank the crankshaft one by one according to the ignition order.

2. Twice adjustment method. ① First, put the cylinder piston at the end of compression, and then the intake valve and exhaust valve of the cylinder must be adjustable. (2) According to the principle of "two in three rows". That is, the intake valve of the second cylinder and the exhaust valve of the third cylinder must be completely closed at this time, and the adjustment can also be checked. ③ Only one pair of valves can be adjusted at a time for two cylinders with connecting rod shaft diameters in the same plane, so the exhaust valve of the fifth cylinder and the intake valve of the fourth cylinder can also be checked and adjusted. ④ When the piston of the sixth cylinder is at the end of compression, the remaining valves that have not been checked and adjusted must be completely closed. Therefore, all valves of the engine can be checked and adjusted by rotating the crankshaft twice.