Cylinders

Cylinder Misalignment

Evidence of this is excessive seal failure, bushing wear, or galling of the piston rod. Often bending of the piston rod or complete failure (breakage) of the rod occurs.

External Leakage

If leakage occurs between the end cap and barrel, check the tie rod torque. If the torque is correct, then replace the barrel seal. When leakage occurs in the rod bushing area, the rod seals should be replaced.

Internal Leakage

Inside the cylinder, leakage past the piston seals can cause sluggish movement or settling of the cylinder under load conditions. This occurs due to leakage of worn piston seals or rings.

Bad Mountings

Due to the wear of pivot pins or mounting bolts working loose, a cylinder may have side load even though the rod was in line when the cylinder was first installed. All cylinder mountings should be checked periodically.

Creeping Cylinder

When a cylinder is stopped in mid-stroke and it creeps, check for internal leakage. A worn control valve can also cause creeping.

Cylinder Sticking or Binding

Check for dirt or gummy deposits or air leaks. Check for misalignment, worn parts or defective packing.

Sluggish Operation During Warm Up Period

The viscosity of oil is too high or the pour point is too high. Change to oil with lower viscosity or better viscosity index and lower a pour point. An immersion heater, placed in the oil, may help under severe cold conditions.

Pilot Control Pressure Too Low

Control line may be too small, or metering choke valve not working properly.

Internal Leakage In Cylinder

Repair or replace worn parts and loose packing. Check oil to see that viscosity is not too low. Check for excessive contamination or wear.

Air In System

Bleed air and check for leaks. Check to see that oil intake is well below surface of oil in reservoir. Check pump packing and line connections on intake side by pouring hydraulic oil over suspected leak. If noise stops, the leak has been located. Tighten joints or change packing or gaskets where necessary.

Repeated Seal Failure

Check for contaminants in oil and cylinder, scored barrel, or damaged shaft.

Rod Seal Failure

Check cylinder alignment and check for bent rod.

Cylinder Creeps Overnight

Carry out rod measurements test. Replace piston seal and check for damaged components.

Implement Valve Leaking

Fit lockout valve or have tractor hydraulics checked.

Uneven Working Depth On Synchronizing Cylinders

Re-phase and purge system of air. Identify where the problem is by carrying out rod measurement test. Replace seal and check for component damage.