CD54 Paving Compactor Caterpillar

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Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. To prevent possible injury, perform the procedure that follows before the test is done.

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Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.

Operational Checks

Note: The checks during operation can be used to find leakage in the system. Operational checks can be used to determine if a valve, a pump, or a motor is bad.

Probable Causes of Problems in the Steering System

Problem

The steering pump is noisy and the steering cylinder rods do not move easily.

Probable Cause

• Air in the steering hydraulic circuit

• The steering pump is worn.

• There is a loose connection in the oil line that is connected to the inlet side of the steering pump.

• The hydraulic oil level is low.

• The strainer inlet in the hydraulic tank is plugged.

• Viscosity of the hydraulic oil is not correct.

Problem

Too much force is needed to turn the steering wheel.

Probable Cause

• The relief valve is open.

• The hydraulic oil level is low.

• The steering pump oil pressure is too low.

• Steering control unit covers are too tight.

• The steering control unit is worn.

• The hydraulic oil is cold.

• The "steering friction" module is shorted to the battery.

• Alignment of steering column is not correct.

• The control valve is restricted or worn.

• One of the steering cylinders is not functioning properly.

• One or both of the valves for the steerlock are fully closed or partially closed.

Problem

The machine does not turn when the steering wheel is turned.

Probable Cause

• The hydraulic oil level is low.

• There is air in the hydraulic system.

• There is dirt in the hydraulic system.

• Steering pump operation is not correct.

• The input signal for the steering is not detected by the ECM.

• One of the valves for the steerlock is fully or partially closed. Both of the valves for the steerlock are fully or partially closed.

• One of the steering cylinders has worn piston rings.

Problem

The machine turns slowly in both directions.

Probable Cause

• There is not enough oil flow from the steering pump.

• One or both of the valves for the steerlock are fully closed or partially closed.

• Steering pump suction line is restricted.

• Steering control unit operation is not correct.

• Seal leakage in the steering cylinders.

• The priority valve spool that is inside the steering pump does not allow enough oil to go to the steering control unit.

• The pressure in the steering circuit is too low.

Problem

Machine turns slowly in one direction.

Probable Cause

• There is a restriction in the steering control unit.

Problem

The steering control unit does not return to the center position correctly.

Probable Cause

• Steering control unit covers are too tight.

• Alignment of the steering column is not correct.

• One of the steering cylinders is not functioning properly.

Problem

Temperature of hydraulic oil is too hot.

Probable Cause

• Viscosity of the hydraulic oil is not correct.

• Air is mixed with the hydraulic oil.

• The relief valve in the steering system has a defect.

• The thermal bypass valve has a malfunction.

• One of the steering system lines has a restriction.

• The oil cooler is plugged.