How to adjust the valve clearance of Isuzu 4JB 1 Euro III engine, and how big is the intake and exhaust clearance?

1. Valve adjustment: first put down the adjusting wires of 1 and cylinder 4 intake rocker arm, turn the crankshaft, turn to cylinder 4 intake rocker arm to nod, do work for 1 cylinder, and turn the crankshaft to the timing position: adjust 1, double, three rows, four rows, and then turn the crankshaft one. Valve clearance: 20 threads are used for intake and 25 threads are used for exhaust.

2. No matter how many cylinders are used to adjust the valve clearance, there is no need to find the top dead center. The method is: turn the flywheel to open the two rocker arms of the cylinder to be adjusted, and then close the begging door. The two rocker arms are parallel, and then rotate a little in the original direction of the flywheel (to prevent the cam from pushing the push rod) to adjust the valve, because the flywheel rotates twice to open the valve once, and the cam will not push the push rod.

3. Remove the intake and exhaust valve chamber cover and magneto cover; Rotate the magneto rotor so that the "T" scribing on its outer circumferential surface is aligned with the scribing on the housing. At this time, the piston should be at the top dead center of the compression stroke; Carefully insert the feeler gauge with the specified valve clearance value into the valve clearance and pull it back and forth. If you feel a little resistance, the gap is appropriate.

Extended data:

Engine classification:

1. According to the working mode of the intake system, it can be divided into four types: natural inhalation, turbocharging, mechanical supercharging and double supercharging.

2. According to the piston movement mode, it can be divided into two types: reciprocating piston internal combustion engine and rotary piston engine.

3. In-line engines, V-type engines, W-type engines and horizontally opposed engine are classified according to cylinder arrangement.

4. According to the number of cylinders, it can be divided into single-cylinder engine and multi-cylinder engine. Modern cars mostly use three-cylinder, four-cylinder, six-cylinder and eight-cylinder engines.

5. According to different cooling methods, it can be divided into water-cooled engine and air-cooled engine. Water-cooled engine is widely used in modern automobile engines because of its uniform cooling, reliable operation and good cooling effect.

6. According to the number of strokes, it can be divided into four-stroke internal combustion engines and two-stroke internal combustion engines. Four-stroke internal combustion engines are widely used in automobile engines.

7. Classification by fuel supply mode: carburetor engine, EFI engine and in-cylinder direct injection engine.