Shear Grapple Arm Circuit

Symptom Problem Solution

Slow In Close Direction

Pilot controller.

See your authorized dealer.

Tree size too large.

See specifications.

Cylinder leakage.

See your authorized dealer.

Worn hydraulic pump.

See your authorized dealer.

Slow In Open Direction

Control valve section.

See your authorized dealer.

Pilot controller.

See your authorized dealer.

Circuit relief valve.

See your authorized dealer.

Worn hydraulic pump.

See your authorized dealer.

Will Not Operate In Either Direction

Worn hydraulic pump.

See your authorized dealer.

Pilot control circuit.

Check controller and lines.

Valve section.

Check spool and end caps for interference.

Will Not Operate In One Direction

Valve section.

Check return spring plug.

Circuit relief.

See your authorized dealer.

Lacks Power

Circuit relief valves.

See your authorized dealer.

Hydraulic pump.

See your authorized dealer.

Left Blade Retracts Before Right Blade And Grapple

Sequence valve.

See your authorized dealer.

Grapple Arms Drift Closed (Valve In Neutral)

Right shear blade not completely opened.

Completely open right shear blade while traveling to next tree.

Cylinder leakage.

See your authorized dealer.

Pilot control circuit.

See your authorized dealer.

Valve leakage.

See your authorized dealer.

Hydraulic line leakage.

Repair or replace.

TX,100,DY2104 -19-10JAN97-1/1