1、 The wiring head of forklift shift solenoid valve is loose or the wire head falls off, and the solenoid valve cannot be energized. The troubleshooting is to tighten the wire head.
2、 The forklift shift solenoid valve coil is burnt out, the solenoid valve does not discharge oil after being powered on, the coil shape is abnormal, and the built-in mandrel of the coil has no electromagnetic suction. Remove the solenoid valve wiring and measure with a multimeter. If there is an open circuit, the solenoid valve coil will be burnt out. The reason is that the coil is damp, resulting in poor insulation and magnetic leakage, resulting in excessive current in the coil and burning. Therefore, it is necessary to prevent rainwater from entering the solenoid valve. In addition, the coil may be burnt out if the spring is too hard, the reaction force is too large, the coil turns are too few, and the suction is not enough. In case of emergency treatment, turn the manual button on the coil from the "0" position to the "1" position during normal operation to open the valve. Or directly replace with a new solenoid valve.
3、 The forklift shift solenoid valve is stuck. The fit clearance between the slide valve sleeve and the valve core of the solenoid valve is very small (less than 0.008mm), which is generally assembled in a single piece. It is easy to get stuck when there are mechanical impurities or too little lubricating oil. The treatment method is to poke the steel wire through the small hole in the head to make it bounce back. The fundamental solution is to remove the solenoid valve, take out the valve core and valve core sleeve, and clean them with CCI4, so that the valve core can move flexibly in the valve sleeve. During disassembly, attention shall be paid to the assembly sequence and external wiring position of each component, so that the reassembly and wiring are correct. It is also necessary to check whether the oil spray hole of the oil mist is blocked and whether the lubricating oil is sufficient.
4、 The forklift shift solenoid valve leaks. External leakage: external leakage may be caused by loose screws or damaged valve parts. The troubleshooting method is to tighten the screw or replace the leaking element. Internal leakage: the solenoid valve cannot be closed after the power is cut off. It is observed on site that the flow still appears when the oil gun is opened after the preset quantity is reached. The reason is that the main valve cannot be closed because the diaphragm is damaged or there is foreign matter in the valve parts. The troubleshooting method is to replace the diaphragm or clean the valve parts. Air leakage will cause insufficient air pressure, making it difficult to open and close the forced valve. The reason is that the sealing gasket is damaged or the slide valve is worn, resulting in gas channeling in several cavities. When dealing with the fault of the solenoid valve of the switching system, it is necessary to select an appropriate time to deal with it when the solenoid valve is powered off. If it cannot be completely dealt with within a switching gap, the switching system can be suspended and dealt with calmly.
5、 The shift solenoid valve of forklift truck is slow to act: it reacts slowly after being powered on and cannot meet the requirements. The reason is that there is foreign matter at the valve or pilot valve, which makes it unable to act flexibly. The troubleshooting method is to clean the valve or pilot valve.
6、 The forklift shift solenoid valve has no small valve function: there is no small flow during preset refueling. The reason is that the large and small flow coils are connected reversely or the pilot valve of the large valve is not closed tightly. The troubleshooting method is to first confirm the wiring mode, ensure that the coil is correctly connected, and then clean the valve or diaphragm.
6、 The flow of the large valve of the shift solenoid valve of the forklift truck is small or does not produce oil: the reason for this fault is that the diaphragm is not fully opened, the pilot valve of the large valve is not fully opened or has no stroke. The troubleshooting method is to clean or replace the large valve pilot valve to ensure the full stroke. At the same time, clean the valve cover channel to ensure that the diaphragm can be opened freely.
7、 The forklift shift solenoid valve opens slowly. Fault cause: 1. Poor sensitivity and slow response of the sensor; 2. The solenoid valve core and valve seat have adhesion and excessive resistance; 3. The pilot hole of pilot solenoid valve (also known as jet solenoid valve) is blocked; 4. Low AC voltage or low battery.
