Piston and connecting rod group, crankshaft and Piston and cylinder liner kit Weichai four matching are the main structural components of diesel engine. The following points should be paid attention to when assembling the piston connecting rod group:
First, press the connecting rod copper sleeve. It is best to use a press or a vice when installing the copper sleeve of the connecting rod. Don't hit it with a hammer; The oil hole or groove on the copper sleeve should be aligned with the oil hole on the connecting rod to ensure lubrication. After the copper sleeve is pressed in, the distance between the two protruding rod ends should be equal.
The second is the clever installation of the piston pin. Piston pin and pin hole interference fit. When installed, the piston should be heated to 90°C ~ 100°C in water or oil. After removing the hammer, place the rod in place between the holes in the piston pin and apply the oiled piston pin as standard. Purpose: To load piston pin holes and connecting rod bushings. At the same time, the piston pin should be pushed while the connecting rod is hooked, and the thumb or the palm of the hand should be shot into the pin hole and the small copper sleeve of the connecting rod, and can be moved in it. The tightness should be recommended. To make the piston pin face equal to the distance between the two piston pin retainers, install the retainers.
Third, the assembly of piston and connecting rod. When assembling pistons and connecting rods, attention should be paid to their relative positions and intended uses. The connecting end of the connecting rod is a plane, and the vortex groove at the top of the piston should be on the same side as the matching number of the connecting rod; The connecting end of the connecting rod is inclined, and the vortex groove at the top of the piston should be at the upper end of the chute. On the same side, there is a tip at the top of the piston which should point towards the injection pump.
4. Install the connecting rod. When the connecting rod group is installed in the cylinder, pay attention to the matching mark on the end of the connecting rod when installing the connecting rod cover, and tighten the bolt with the torque wrench 2 ~ 3 times according to the defined torque. The moving crankshaft should not be stuck, and finally install a tight wire or fuse.
Fifth, the piston ring installation. Pay attention to the position and number of each piston ring when installing them. The first gas ring on the piston is usually a chrome ring. The second and third rings are mostly twisted rings, but there are also conical rings. If there is a ring of slang in it, the slang should be facing down; In the case of tapered rings, the Angle of the side or cone with the word "up" should be facing up. The piston ring shall not be stuck in the groove; The opening of the first gas ring shall not be opposite to the pin hole of the piston and the vortex groove at the top of the piston; The opening positions of the adjacent rings should be staggered by 90-120 degrees to prevent cylinders. Gas leakage, easy to seal. After the piston ring is installed, check the opening (end clearance) and side clearance. The gap between teeth is easy to cause air leakage, and the gap is too small, will occur tooth adhesion phenomenon; The side clearance refers to the gap between the piston ring and the ring groove in height, so that the piston ring can move freely in the ring groove, so as not to get stuck. The gap should not be too wide. Otherwise, when the piston moves up and down in the cylinder, the gas ring will be flooded by the pump oil, and the lubricating oil will enter the combustion chamber, accelerating the wear of the lubricating oil and causing serious carbon deposition.
