Paccar CARCO 50B, Service Manual

Page: 16 / 61

14
P
390/410 PSI
15 PSI
F
LG L
BRAKE LUBE
& COOLING
ORIFICE
LUBE
FS
315/370
PSI
PS
A
1
C2 BR C1
15 PSI
REEL OUT
CLUTCH
BRAKE
REEL IN
CLUTCH
ORIFICE
ORIFICE
PRESSURE
SWITCH
ACCUMULATOR
FS
BULL GEAR
PUMP
FILTER
SUCTION
STRAINER
A
C2 BR C1
SYS
2
3
13
4
6
7
11
9
12
O O O O O O O LOW PRESSURE
HIGH PRESSURE
10
GREEN (9)
FILTER
HEAD A
A
PS
BR
C2
FS
C1
RED (1)
BROWN (4)
ORANGE (7)
BLACK (11) - GROUND
BLUE (2)
WHITE (6)
WHITE W/ BLACK STRIPE (3)
BLACK (11) - GROUND
12 11 10 9 8 7
6 5 4 3 2 1
(-) GROUND
(+) 24 VDC (+) 24 VDC, SLOWLY
CYCLING ON-OFF
(ON WHILE CHARGING,
BREAK-ON (NEUTRAL) "CHARGING"
When "charging", 24 volts DC will be seen at the red and
blue wire within the winch case, and at terminals 1 and
2 at the diagnostic connector. The blue wire and pin 2
will be de-energized when the circuit is "unloaded".
The pressure maintenance system operates continuous-
ly to maintain a stand-by supply of oil pressure for the
control system. The pressure maintenance system con-
sists of the following components:
Item 9 - Check Valve
Item 10 - Main Pressure Solenoid Valve
Item 11 - Stand-by System Pressure Switch
Item 13 - Accumulator Holding Cartridge (not
found on early units)
Item A - Accumulator
Oil from the pump passes through the filter and enters
the valve housing, passing through the check valve (9)
and holding cartridge (13) on its way to the accumulator
(A). When charging first occurs, the pressure switch (11)
contacts are closed producing a signal to energize the
main pressure solenoid (10) to block the flow of oil to the
lubrication circuit. At this time, all of the oil from the pump
is directed to fill the accumulator and the pressure
gallery in the control valve.
CONTROL VALVE DIAGNOSTICS PLUG
BRAKE ON (NEUTRAL) “CHARGING”