CY-A8V107ER-type hydraulic pump 4 cases troubleshooting

When the CY-A8V107ER type hydraulic pump failure, careful examination, analysis, symptomatic treatment, to avoid the demolition of large demolition into a new fault. 1, the pump body heat, low work efficiency (1) hydraulic oil poor quality, low viscosity should be replaced DTE25 (Mobil) or HM-N68 (Great Wall) hydraulic oil, but can not be mixed. (2) parts of the pump contact surface damage ① The use of the pump is a spherical face plate, when the cylinder with a slight pull on the mating surface with the grinding paste with research; when the deep marks should be First fill the trench, with research. Installation, should pay attention to calculate the thickness of the gasket, which must be measured before the grinding plate and the distribution plate and the total thickness of the cylinder block, calculated by the thickness of the mill to be in the mandrel butterfly gasket adjustment Gaskets, the compensation is obtained by grinding the thickness; When the face plate and cylinder with serious wear and tear, should immediately replace the new pieces. ② The standard clearance between plunger and cylinder is 25 ~ 26μm. During the period of more than 60μm, will increase the collision between the plunger and the cylinder, and the leakage will increase, the volumetric efficiency will be reduced, this time should be repaired and replacement. Also note that: When replacing the copper sleeve is best used frozen copper sleeve, or the method of heating the cylinder interference fit, so that the installation is relatively easy, and can avoid damage caused by percussion. (3) poor cooling of hydraulic oil hydraulic oil should be checked after three hot gas pipeline is unobstructed, and check whether the radiator is working properly. 2, the system piping fierce jitter, noise, and accompanied by a very thin scream (1) bearing damage When the bearing transition damage or damage, it will cause vibration and abnormal sound, the bearings should be promptly replaced. Now introduce a common method of disassembling the bearing: first remove the fixing bolt of the regulator housing, remove the regulator housing, and remove the valve plate and the pump body at a time; then loosen the auxiliary input shaft on the pump housing Screw plug, and use a round hole equivalent to tap the end of the secondary input shaft, push it out of the pump body; finally remove the retainer on the main input shaft, remove the cap on the shaft, and then use copper Rod hit the end of the spindle, remove the spindle can be. When installing a new bearing, the reverse order is as above. (2) less fuel tank, pump empty. Add the right amount of hydraulic oil can. (3) hydraulic pump has a very scream This phenomenon occurs mainly in high altitude. In August last year, a hydraulic excavator equipped with this type of hydraulic excavator in our department was working normally in the plains. However, when hydraulic adaptability test was carried out in plateau at a place above 4500m above sea level in Xinjiang, the hydraulic pump screamed Sound, after multi-search, originally, the pump inlet pressure is too small.To this end, if the hydraulic tank port plus a breathing valve, the hydraulic tank to produce a certain amount of preparatory pressure, which can increase the pressure of the pump inlet , Screams can be ruled out. (4) hydraulic pump suction pipe leakage, resulting in the air into the pump should be excluded from the air, rust or replace the pump oil pipeline.