How the unit pump of the tractor fuel pump is assembled

1, tractor fuel pump unit pump assembly sequence is as follows: (1) the new plunger pair and all parts clean. (2) Insert the oil outlet valve together with the gasket into the corresponding hole of the unit pump housing (the unit pump housing is equivalent to the plunger sleeve). When loaded, the valve seat should be large toward the outside. Then, install the oil valve spring, reduce the volume, and finally install the oil valve seat and tighten, tightening torque of 70 Newton meters. (3) Install sealant Install the sealant into the corresponding groove of the pump casing, and then turn the rubber ring with your finger to eliminate the distortion. (4) Installing the plunger Hold the pump housing in the hand with the head facing forward. When the inlet is on the right, the tail of the plunger is marked with a flat side upwards, then insert the plunger into the corresponding hole of the pump housing , And then install the fan gear sleeve, and the plunger from the fuel supply fan gear corresponding slot down. If you can not pull down, you can gently turn the tail of the plunger, you can pull down. (5) When assembling the retaining ring, the spring and the lower spring retaining ring, make sure that the tongue on the retaining ring reliably falls into the corresponding hole in the unit casing, then install the plunger spring and the lower spring seat. When all parts of the unit pump are properly assembled, when the plunger spring is pressed horizontally, the oil supply sleeve should rotate left and right flexibly. 2, the unit pump to the injection pump housing installation (1) the pump unit pump mounting hole clean, and painted with fresh oil, so that the assembly is smooth, to avoid injury unit pump seal rubber ring. (2) The fuel pump lever to the maximum position, when the fuel supply front end of the gear rod touch the front end of the fuel pump plug does not move forward, this time, the fuel gear just protrude the fuel pump front end 7 mm. (3) Apply fresh oil to the unit pump sealant ring and oil fan gear sleeve. Hold the unit pump in your hand with the head facing outwards and the inlet hole on the unit pump housing on the right and the missing tooth centerline on the fuel fan gear sleeve to the direction of the long axis of the unit pump mounting flange Coincides with the center line. (4) Put the unit pump oil fan gear sleeve against the unit pump mounting hole and feed the gear rod direction first, and then press the unit pump with the palm of your hand. When the last seal ring on the unit pump enters the hole When the distance between the unit pump fixed flange lower plane and the injection pump upper plane is about 2.7 mm), this indicates that the lack of teeth on the feed fan gear sleeve on the unit pump has been matched with the wide tooth profile Engage, this time need to use the first wooden handle tap unit pump, make it fully seated. If the force of the palm of the hand can not press the last seal of the unit pump into the hole (at this time, the distance between the lower surface of the unit pump fixing flange and the plane of the fuel injection pump is about 4.7 mm) It shows that the oil fan gear sleeve has not engaged with the oil supply gear rod. In such a case, the unit pump can be slightly pulled out and the left and right micro-rotation unit pumps can be reassembled to solve the problem under normal circumstances. Install a unit for each pump, when turning the joystick, the fuel supply gear should be able to move flexible, non-stagnation, or should identify the cause. If the phenomenon of stagnation, the general is due to the teeth on the fan gear sleeve injury caused by trimming the teeth, you can solve the problem. When the four unit pumps are fully assembled, when the fuel injection pump control lever is turned on, the oil supply gear rod (before this, the screw plug on the front end of the oil supply gear rod should be removed) should move forward and backward with sensitivity, When the throttle is in the position, the length of the feed rod to extend beyond the front face of the injection pump is about 10.5 mm. When the control rod is in the stop position, the oil supply rod should be retracted to about 10 mm in front of the fuel injection pump. If the oil supply gear rod extension is too small, indicating that the oil supply gear rod movement resistance should check whether there is damage to the fuel fan teeth, the piston with the gap is too small and so on. If the supply lever is undersized by less than 6.5 mm, this indicates that the supply lever is not in the correct engagement with the supply fan gear and the unit pump should be reassembled.