DESCRIPTION
The cooling system regulates engine operating temperature. It allows the engine to reach normal operating temperature as quickly as possible, maintains normal operating temperature and prevents overheating.
The cooling system also provides a means of heating the passenger compartment. The cooling system is pressurized and uses a centrifugal water pump to circulate coolant throughout the system. A separate and remotely mounted, coolant bottle is used.
OPERATION
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 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. On the gas engine coolant flows through the engine, radiator, heater, and water pump.
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.
| WARNING | The automatic belt tensioner assembly is spring loaded. Do not attempt to disassemble the tensioner assembly. |
The automatic belt tensioner maintains correct belt tension using a coiled spring within the tensioner housing. The spring applies pressure to the tensioner arm pressing the arm into the belt, keeping the belt tight. The belt tensioner will maintain positive pressure on the back side of the belt at all times including engine load and engine speed changes. It is normal to observe torsional variances while the engine is running.
| CAUTION | Mopar® Antifreeze/Coolant, is a Lifetime of Engine Formula. IT MAY NOT BE MIXED WITH ANY OTHER TYPES OF ANTIFREEZE. Mixing of coolants other than specified (non-OAT or other OAT), may result in engine damage that may not be covered under the new vehicle warranty, and decreased corrosion protection. |
To find the coolant needed. Refer to CAPACITIES AND RECOMMENDED FLUIDS, SPECIFICATIONS .
| WARNING | Antifreeze is an ethylene-glycol base coolant and is harmful if swallowed or inhaled. If swallowed, drink two glasses of water and induce vomiting. If inhaled, move to fresh air area. Seek medical attention immediately. Do not store in open or unmarked containers. Wash skin and clothing thoroughly after coming in contact with ethylene-glycol. Keep out of reach of children. Dispose of glycol base coolant properly, contact your dealer or government agency for location of collection center in your area. Do not open a cooling system when the engine is at operating temperature or hot under pressure, personal injury can result. Avoid radiator cooling fan when engine compartment related service is performed, personal injury can result. |
| CAUTION | Mixing of engine coolant (antifreeze) other than specified Organic Additive Technology (OAT) engine coolant (antifreeze), may result in engine damage and may decrease corrosion protection. Organic Additive Technology (OAT) engine coolant is different and should not be mixed with Hybrid Organic Additive Technology (HOAT) engine coolant (antifreeze). If a non-OAT engine coolant (antifreeze) is introduced into the cooling system in an emergency, it should be replaced with the specified engine coolant (antifreeze) as soon as possible. |
The cooling system is designed around the coolant. The coolant must accept heat from engine metal, in the cylinder head area near the exhaust valves and engine block. Then coolant carries the heat to the radiator where the tube/fin radiator can transfer the heat to the air.
The use of aluminum cylinder blocks, cylinder heads, and water pumps requires special corrosion protection. Mopar® Antifreeze/Coolant, or the equivalent ethylene-glycol base coolant with organic corrosion inhibitors (called OAT, for Organic Additive Technology) is recommended. This coolant offers the best engine cooling without corrosion when mixed with 50% ethylene-glycol and 50% distilled water to obtain a freeze point of -37°C (-35°F). If it loses color or becomes contaminated, drain, flush, and replace with fresh properly mixed coolant solution.
| WARNING | Hot, pressurized coolant can cause serious burns. Allow the system to cool down and decrease pressure prior to any service being performed. |
The after-run pump is used to circulate coolant though the cooling system when the key is off and a predetermined temperature is reached. The primary reason for the pump is to help cool the turbocharger to help prevent damage due to heat soaking. The after-run pump is free spinning in the Key ON, Engine ON condition and activated during Key OFF, Engine OFF condition for up to 10 minutes. The pump draws coolant in from the thermostat housing and sends it to the turbocharger when activated. The Powertrain Control Module (PCM) controls the operation of the pump. The inputs to determine pump operation include engine coolant temperature, throttle position and engine off time.
The automatic transmission cooler is located in the front of the condenser and behind the front fascia. The transmission cooler is a heat exchanger that allows heat in the transmission fluid to be transferred to the air passing over the cooler fins.
The Transmission oil cooler assembly is equipped with quick connect fitting for the transmission oil cooler lines.
Transmission oil is routed through the cooler where heat is removed from the transmission oil before returning to the transmission.
Scheme 1
Scheme 2
- Raise and support the vehicle. Refer to «HOISTING, STANDARD PROCEDURE»(ref-646211-S00664313032014072800000) .
- Remove the belly pan and closeout panel. Refer to «BELLY PAN, REMOVAL»(ref-646214-S24731623582014072800000) .
- Loosen the cooler line bracket bolt to allow for line movement.
- Release the lines from the cooler at the cooler quick connects (1).
- Pinch the four expanders to allow the cooler retainers (1) to be slid forward away from the radiator assembly.
- Remove the transmission oil cooler from the vehicle through the bottom.