Thermo King 920000, Manual

Page: 49 / 190

Operating Instructions
49
Engine Low Oil Pressure Cutout:
The engine low
oil pressure cutout is a pressure sensitive switch
located in the engine oiling system. This switch
will trip the Engine Reset and stop the engine if
the oil pressure drops below 8 to 12 psi
(55 to 83 kPa).
Refrigerant High Pressure Cutout:
The high
pressure cutout is a pressure sensitive switch
located in the compressor head. If the refrigerant
discharge pressure exceeds the current setting,
this switch opens the circuit to the fuel solenoid,
stopping the engine. Within 30 to 50 seconds, the
engine reset will also trip because of no oil
pressure in the engine. For Model 50 units, this
switch also shuts down electric motor operation.
Refrigerant High Pressure Relief Valve:
This valve
is designed to relieve excess pressure within the
refrigeration system. Located on a high pressure
line near the condenser, it is non-repairable and
requires no adjustment. When pressure is released
from the valve, it is directed away from anyone
servicing the unit.
Preheat Buzzer (CYCLE-SENTRY Units):
The
preheat buzzer sounds when the
CYCLE-SENTRY system causes the glow plugs
to preheat.
Unit Operation
Pretrip Inspection
Pretrip inspections are a very important part of
regularly scheduled preventive maintenance
programs designed to minimize operating
problems and breakdowns before they happen.
While pretrips are not intended to take the place
of regular maintenance inspections, the following
suggested pretrip inspection should be performed
before every trip involving refrigerated cargo.
Fuel:
The diesel fuel supply must be adequate to
guarantee the operation of the engine to at least
the next check point.
Engine Oil:
The engine oil level should be at the
FULL mark on the dipstick. Never overfill.
Coolant:
Check coolant level gauge for the correct
amount of coolant. The indicator should be in the
FULL (white) range. If the coolant level is in the
ADD (red) range, add coolant to the expansion
tank. The coolant should be a 50/50 mixture of
ethylene glycol and water and provide protection
to -30 F (-34 C).
Battery:
The terminals must be tight and free of all
corrosion. Electrolyte should be at full mark.
Belts:
The belts must be in good condition and
adjusted to the proper tension. Allow 1/2 inch
(13 mm) deflection at the center of the span
between pulleys.
Electrical:
Check all electrical connections to
make certain they are securely fastened. Wires
and terminals should be free of corrosion, cracks
or moisture.
Structural:
Visually inspect the unit for leaks,
loose or broken parts and other damage.
Gasket:
The unit mounting gasket should be
tightly compressed and in good condition.
Coils:
The condenser and evaporator coils should
be clean and free of debris.
Cargo Box:
Inspect the interior and exterior of the
box for damage. Any damage to the walls or
insulation must be repaired.
Defrost Drain:
Check the defrost drain hoses and
fittings to be sure they are open.
Doors:
Be sure doors and weather seals are in
good condition, door latches securely and weather
seals fit tightly.
CAUTION: Do not remove the expansion
tank cap while the coolant is hot.