THEORY OF OPERATION - CONTINUED
NONELECTRICAL GAUGES, INDICATORS, AND DIPSTICKS - CONTINUED
Fuel Level Dipstick. Dipstick
in fuel fill opening. Calibrations show FULL, EMPTY, and
percentage of fuel
Refer to Hydraulic System in this work package for hydraulic system operation and location of hydrau-
lic system components related to blade system operation.
Refer to TM 5-3805-261-10 for blade operation instructions and location of blade controls.
The blade system uses hydraulic cylinders and a hydraulic circle drive motor to move the blade. The hydraulic system
provides power for the cylinders and motor. The blade control levers are located at the sides of the steering console in
the cab. The blade centershift lock is powered by pressurized air.
When the engine is running, the oil from the variable displacement pump goes through the relief and pressure reduction
valves, through lines to the control valves for the blade system cylinders. The pressure of the oil can get as high as the
pressure setting of the relief valve. When the control valves for the blade system cylinders are not being used, the pres-
sure of the oil is 2,150 psi (14,824 kPa).
When the engine is running and the cylinders are not being used, the pressure of the pump oil in lines to the control
valve is approximately 2,150 psi (14,824 kPa). The oil in lines and passage is open to the tank and the pressure of the oil
in these lines is the same as the oil in the tank. The lock check valve stops the oil in the lines between the pressure reduc-
tion valve and the cylinder and the rod in the cylinder cannot move.
When the blade control valve lever for the cylinder is held in the forward position, the pump oil goes through the control
valve through lines and the lock check valve into the head end of the cylinder. The oil in the head of the cylinder pushes
the piston and rod out of the cylinder, which moves the blade. When more force is needed, there is an increase in the
pressure of the pump oil to the head end of the cylinder. When the pressure of the pump oil goes to 1,500 psi (10,342
kPa), the oil moves the shuttle valve in the pump and the oil pressure from the pump can go to approximately 3,500 psi