Check all oil lines, all hoses, and all connections for
damage and for leaks. Look for oil on the ground under
If oil can leak out of a fitting or out of a connection,
air can leak into the system. Air in the system is as
harmful as having too little oil.
SMCS Code: 4300-035
Personal injury or death can result from sudden machine
Sudden movement of the machine can cause injury to
persons on or near the machine.
To prevent injury or death, make sure that the area around
the machine is clear of personnel and obstructions before
operating the machine.
Personal injury can result from hydraulic oil pressure and
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.
Care must be taken to ensure that fluids are contained
during performance of inspection, maintenance, testing,
adjusting and repair of the product. Be prepared to collect
the fluid with suitable containers before opening any
compartment or disassembling any component containing
Refer to Special Publication, NENG2500, "Caterpillar Tools
and Shop Products Guide" for tools and supplies suitable
to collect and contain fluids on Caterpillar products.
Dispose of all fluids according to local regulations and
The checks during operation can be used to find
leakage in the system. These checks can also
be used to find a bad valve, a bad pump, or a
Probable Causes of Problems in the Steering System
The gear pump is noisy and the steering cylinder rods do
not move easily.
Air in the steering hydraulic circuit.
The gear 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.
Viscosity of the hydraulic oil is not correct.