Care must be taken to ensure that fluids are contained
during performance of inspection, maintenance, testing,
adjusting and repair of the machine. Be prepared to
collect the fluid with suitable containers before opening
any compartment or disassembling any component
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
Leveling Blade Cylinder
(1) Hose. (2) Cylinder rod end port.
Disconnect hose (1). Install a tee at cylinder rod end
port (2). Connect a 25000 kPa (3600 psi) pressure
gauge to one end of the tee. Connect hose (1) to the
other end of the tee. This gauge measures the pressure
setting of the relief valve.
Start the machine and run the engine at high idle at
2350 50 rpm until the hydraulic oil temperature
reaches 38C (100F).
Pull the blade control lever back to the RAISE position.
Keep the blade control lever in the RAISE position after
the blade is completely raised. Read the pressure on
the gauge. The pressure should be 600 345 kPa
(1247 50 psi).
Leveling Blade Control Valve
(3) Control valve. (4) Relief valve. (5) Protective nut.
The relief valve (4) must be adjusted if the pressure is
Remove nut (5) from relief valve (4). Loosen the locknut
and turn the adjustment screw clockwise in order to
increase the pressure setting. Turn the adjustment
screw counterclockwise in order to decrease the
Check the relief valve pressure setting again. If the
pressure is correct, tighten locknut (6) and install nut (5).
Remove the pressure gauge and the tee. Reconnect
the hose (1) to the cylinder rod end port (2).
(Leveling Blade) - Test
SMCS Code: 6060-081-CD; 6151-081-CD
ORFS Fittings Group
Escaping fluid under pressure, even a pinhole size leak,
can penetrate body tissue, causing serious injury, and
possible death. If fluid is injected into your skin, it must
be treated immediately by a doctor familiar with this type
Always use a board or cardboard when checking for a