Alamo MACHETE Product Service Manual page 18

CONTROL VALVE - OPERATION
HYDRAULIC LOCK VALVE: (Head Tilt Function)
An Electric Solenoid Operated Hydraulic Lock Valve (Figure 3) is incorporated in the Head Tilt
Function to prevent excessive (Head Lift Cylinder) leak down during storage or transportation.
The Solenoid which operates this valve is normally in the Locked position until Head Lowering
function is actuated at Joystick. When Joystick is actuated to lower Head an electric signal
is sent to solenoid to open Lock valve. When the function to raise the Head is activated there
is no electric signal from Joystick. The pressure against the valve when head is being raised
will force Valve open like a relief Valve allowing Oil to pass through it. If this valve will not open
it could stop head from lifting or dropping. The valve is plumbed into the Hydraulic Circuitry of
the Head Tilt Function and is located near the Control Valve.
ELECTRIC SIGNALS:
Electrical Signals are sent to the Controllers etc. through a Wiring Harness, The Harness
is supplied with a one way connector at the Joystick Console Box (So it can not be installed
Wrong). Connectors are supplied for each electric valve controller connection, These are
labeled (with Letter code A,B,C etc.) for the function which they are connected. The Plug
will only fit together one way and should always have right connections. BUT if the terminals
within this Plug are moved around or the connections at the valve end are changed then
the Plug would still be connected the same way and be Wrong. If any connections are
removed they MUST be placed back in the same order they came out of. (SEE FIGURE
5 and 6) See Figure 6 for Plug Connection (Letter Code)
Wiring Schematic, BUT NOTE on the Wiring Schematic it WILL NOT be the actual
location of Wires (Letter Codes ABC etc.), They are changed to enable the wiring
diagram to be drawn with as few lines crossing each other as possible for illustration
purposes.
See Figure 6 for actual Wire locations in Plug.
DO NOT USE WIRE SCHEMATIC PIN LOCATION IN PLUG TO MAKE
CONECTIONS IN ACTUAL PLUG.
DO NOT CHANGE LOCATIONS OF PINS AND/OR WIRES IN PLUGS, THEY
MUST BE CONNECTEDTHE SAME WHEN REPLACED OR THE SYSTEM
WILL MALFUNCTION AND THIS COULD ALSO DAMAGE JOYSTICK
CONTROLLER COMPONENTS.
MACHETE (Service Manual) 04/04
© 2004 Alamo Group Inc.
Hydraulic Lock Valve
FIGURE 3
& Terminal locations, Also the
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