6. ATTACHMENT SYSTEM 6. ATTACHMENT SYSTEM BOOM OR ARM ACTION IS IMPOSSIBLE AT ALL BOOM OR ARM ACTION IS IMPOSSIBLE AT ALL 1) 1) 5-17 YES Does the symptom change YES when port relief valve is replaced Is MCV pilot with other valve? NO YES pressure within standard level? Inspect if pilot piping is not OK clogged or oil is NO Are other not leaking from YES attachments the piping. operatable? YES Is gear pump pilot pressure NO Is gear pump NO within standard delivering oil? level? NO Is travel operations OK possible? Disassemble YES main relief valve Remove dust plug and check if it is under engine not irregular.
OK flywheel and Faulty check if coupling element particles Inspect oil are not present. Particles present volume in NO hydraulic oil tank. Short YES Does control ⓐ valve spool move lightly by hand? NO Cause Remedy Port relief valve is faulty. Disassemble and repair or replace. Disassemble and repair. Disassemble and repair or replace. Disassemble and repair. Disassemble and repair. Disassemble and repair or replace. Disassemble and repair. Replenish hydraulic oil. Disassemble and repair. Disassemble and repair. ⓐ Pilot valve is faulty. Pilot relief valve is faulty. Gear pump is broken. Hydraulic pump is broken. Main relief valve is defective. Coupling at pump connection is broken.
Cylinder interior is broken. Control valve spool is stuck.