Broderson IC-200-2H, Operation And Maintenance Manual

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BOOM AND OUTRIGGER CIRCUIT:
The relief valve pressure setting at the inlet for boom control sections is 2600 PSI (179 bar)
for IC-200-1 & 2, 3000 PSI (207 bar) for IC-200-3. This pressure is required for all but the
swing control section. Two work port relief valves are installed in the swing section. These
relief valves are set at 1500 PSI (103 bar).
The relief pressure at the inlet end of the valve can be adj usted with a wrench and an allen
wrench. Loosen the nut and tighten the threaded stem with an allen wrench to increase pres-
sure, and loosen t he stem to decrease pressure. Lock in place w ith the nut. Actuate the
BOOM LOWER or TELESCOPE RETRACT function with the cylinder fully retracted when
making this adjustment.
While the pressure gauge is attached, the swing function may be checked by capping the two
work ports of the swing section and actuating the swing control lever in each direction. If the-
se pressures are improper, the work port relief valve can be removed and shims added or re-
moved as needed. Part numbers for the work port relief valves and shims are listed below:
9-340-00070 Work Port Relief Valve-Gresen #7460-002 PS 1500 C
9-340-00032 Shim -- .010" -- Gresen #0462-001
9-340-00031 Shim -- .020" -- Gresen #0459-001
9-340-00030 Shim -- .040" -- Gresen #0458-001
(Pressure is changed approximately 100 to 125 PSI (7 to 9 bar) for each .010" shim).
BOOM CYLINDER HOLDING VALVE:
A holding valve is directly connected to the base of the boom lift cylinder barrel and t o the
base of the primary telescope cylinder rod. These valves are designed to hold the boom in
position should loss of power or pressure line failure occur.
To check the boom lift cylinder holding valve, set the outriggers, place the boom in the hori-
zontal position over the front of the crane and raise rated load about six inches (15 cm) above
the ground using the boom lift cylinder (not the hoist). The best load for this test is the rated
load at the 16 foot (5.0 m) load radius with outriggers extended and the boom over the front.
Turn the engine off and move the BOOM lever to the LOWER position. If the boom moves
down, adjust the holding valve.
W A R N I N G
Before working on the holding valves or plumbing to the boom lift cylinders, always
relieve trapped pressure by lowering the boom fully, turning off the engine, and cycling
the BOOM lever.
To adjust the holding valve, loosen the jam nuts on the adjusting screw and tighten the screw
until unpowered boom movement stops. Retighten the jam nuts. If adjusting the valve does
not help, the cylinder may have internal leakage or the valve may be malfunctioning.
Courtesy of Crane.Market