In the maintenance manual hydraulic pump from the following to find the cause, and to improve the system: 1. Check the boom cylinder internal leakage situation. The easiest way is to raise the boom bidirectional hydraulic hand pumps, to see whether there is a significant decline in freedom 2, if you disassemble the fuel tank to check the whereabouts of obvious, such as worn seals should be replaced. 3, check the control valve. First clean the safety valve, check valve wear, such as wear and tear should be replaced. 4. If there is still no change after installing safety valve hydraulic hand pump seals, and then check the control valve spool wear, the gap is generally limits the use of 0.06mm hydraulic hand pump pictures, badly worn should be replaced. 5, the measurement manual hydraulic pressure. If the pressure is low, then make adjustments, plus the pressure is still not tune up, then the manual pump badly worn Model Working pressure MPa maximum displacement MI / second maximum hand force N Fuel tank capacity L Weight KG main exterior reference dimensions (mm ) Note (1) Note (2) High Low High Low LL1BB1HSYB-16312.312.5≤5000.7 7640560140110160 single double pump the oil with SYB-1SYB-26312.312.5≤500310650550140100140 single double pump the oil with SYB-2SYB-2A6312.312.5≤ 500411700600140100140 pairs with the oil pump single SYB-2ASYB-3S6312.312.5≤450311 650600140100160 double-pump double the oil with a manual valve SYB-2S-A6312.315≤4501.510 650600140100160 double-pump double the oil with a manual valve 3JTB-16312.312 .5≤500311700600140100140 double pump the oil hydraulic hand pump single picture, Lu Hydraulic (certified), Langfang hydraulic hand pumps provided by the Texas Lu force hydraulic machinery plant. Texas Lu force hydraulic machinery plant (www.luliyeya.com) is a leader in Dezhou, hydraulic machinery and parts, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Lu Hydraulic leadership with the staff warmly welcome all inquiries negotiations to create Lu hydraulic force a better future.