The disassembly and assembly of the main Hydraulic Pump is a major project,and many new pumps are quickly damaged,mostly due to errors in disassembly details.Strictly follow the process to avoid early wear and tear of new parts.

　　Turn off the engine and stop the machine before disassembly,wait for the hydraulic oil to cool down sufficiently,release the residual pressure in the system,and disconnect the negative terminal of the battery.Drain the hydraulic oil from the hydraulic oil tank,remove the hydraulic pump inlet pipe,high-pressure outlet pipe,drain pipe,and pilot control pipe,and mark the pipelines.Disassemble the connecting housing,separate the engine flywheel from the hydraulic pump drive end,remove the fixing bolts,and lift out the Hydraulic Pump Assembly.

　　After disassembling the old pump,if the old pump has worn out and produced a large amount of metal debris,it is necessary to clean the hydraulic oil tank,flush the entire hydraulic pipeline,and replace all hydraulic filter elements(return oil,suction oil,Pilot Filter elements).Metal impurities remaining in the system can directly strain the friction pair of the new pump.

　　Before installing the new pump,check the part number and ensure that the drive spline is intact.Apply lubricating grease to the drive splines.During installation,the pump and engine should be connected coaxially,and it is forbidden to forcefully pull bolts to align them.Different shafts can cause rapid damage to the drive shaft and splines.Tighten the bolts diagonally in stages according to the standard torque.

　　Install all oil pipes,replace all O-ring seals with new ones,and prohibit the reuse of old seals.The oil inlet pipeline must be tightly sealed.If there is a leak in the oil inlet pipeline,air will be sucked in,causing cavitation and quickly damaging the pump.The oil drain pipe should be installed smoothly and should not be flattened,bent or blocked.If the oil drain is blocked,the internal pressure of the pump will rise and directly penetrate the seal.

　　After assembly,add qualified hydraulic oil and exhaust the air in the hydraulic system.Start the engine and let it idle first,observe if there is any abnormal noise or oil leakage from the pump;Gradually test each action,use a pressure gauge to detect system pressure and regulator power,and debug to the original factory standard.

　　High frequency fault points during disassembly and assembly:uncleaned fuel tank pipeline,intake pipeline,hard installation of different shafts,and blocked drain pipe.Proper cleaning,centering installation,sealing replacement,and exhaust debugging are necessary to ensure the stable operation of the hydraulic pump.