Cooling System: Description and Operation
COOLINGDESCRIPTION
Engine Cooling System Flow - 3.7L/4.7L:
GAS ENGINE
The 3.7L/4.7L engine cooling system consists of
^ LH Cylinder Head (1)
^ Bleed (2)
^ Thermostat location (3)
^ RH Cylinder Head (4)
^ RH Bank Cyl. Block (5)
^ LH Bank Cyl. Block (6)
^ Coolant Temp Sensor (7)
^ From Heater Core (8)
^ To Heater Core (9)
The cooling system regulates engine operating temperature. It allows the engine to reach normal operating temperature as quickly as possible. It also maintains normal operating temperature and prevents overheating.
5.7L Engine Coolant System Flow:
The 5.7L engine cooling system consists of
^ LH Cylinder Head (1)
^ To Radiator (2)
^ From Radiator (3)
^ To RH Cylinder Head (4)
The cooling system provides a means of heating the passenger compartment and cooling the automatic transmission fluid (if equipped). The cooling system is pressurized and uses a centrifugal water pump to circulate coolant through the system. The coolant recovery/reserve system utilizes an ambient overflow bottle
8.3L Cooling System
8.3L Cooling System:
The 8.3L engine cooling system consists of
^ Thermostat Housing (1)
^ Controlled Flow Thermostat (2)
^ Water Pump (3)
^ Radiator (4)
^ Pressure Bottle To Water Pump (5)
^ Pressure Bottle To Radiator (6)
^ Coolant Recovery Bottle (7)
^ Pressure Bottle To Coolant Recovery Bottle (8)
^ Coolant Pressure Bottle With Pressure Cap (9)
^ Heater Core (10)
^ Control Valve (11)
An optional factory installed maximum duty cooling package is available on most models. This package will provide additional cooling capacity for vehicles used under extreme conditions such as trailer towing in high ambient temperatures.
5.9L DIESEL
Cooling System Circulation - 5.9L Diesel Engine:
^ The diesel engine cooling system consists of:
^ Cross-flow radiator
^ Belt driven water pump
^ Cooling fan (attached to the electronic viscous fan drive)
^ Belt driven Electronic viscous fan drive
^ Engine mounted fan shroud
^ Radiator pressure cap
^ Vertically mounted thermostat
^ Coolant reserve/recovery system
^ Engine mounted Transmission oil cooler (Automatic Only)
^ Radiator mounted fan shroud
^ Coolant
HOSE CLAMPS
The cooling system utilizes spring type hose clamps. If a spring type clamp replacement is necessary, replace with the original Mopar equipment spring type clamp.
CAUTION: A number or letter is stamped into the tongue of constant tension clamps. If replacement is necessary, use only a original equipment clamp with matching number or letter and ensure the clamp has the same size width.
OPERATION
COOLING SYSTEM
The cooling system regulates engine operating temperature. It allows the engine to reach normal operating temperature as quickly as possible. It also maintains normal operating temperature and prevents overheating.
The cooling system also provides a source of hot water (coolant) for heating the passenger compartment and cooling the automatic transmission fluid (if equipped). The cooling system is pressurized and uses a centrifugal water pump to circulate coolant throughout the system.
^ When engine is cold the thermostat is closed. The cooling system has no flow through the radiator. The coolant flows through the engine, water pump, and heater.
^ When engine is warm the thermostat is full open. The coolant flows through the engine, radiator, heater, and water pump.
All engines utilize an ambient overflow bottle for coolant recovery/reserve.
An optional factory installed maximum duty cooling package is available on most models. This package will provide additional cooling capacity for vehicles used under extreme conditions such as trailer towing in high ambient temperatures.
HOSE CLAMPS
The spring type hose clamp applies constant tension on a hose connection. To remove a spring type hose clamp, only use constant tension clamp pliers designed to compress the hose clamp.