Engine Cooling System: Overview Jeep Compass I рестайлинг

DESCRIPTION

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 consists

1. Radiator
2. Coolant
3. Electric cooling Fans
4. Water pump
5. Thermostat
6. Charge air cooler (Turbocharged vehicles only)
7. In-radiator Power steering oil cooler (Turbocharged vehicles only)
8. Hoses and clamps
9. Transmission oil cooler
10. Coolant pressure bottle/overflow system

The automatic belt tensioner maintains proper tension on the accessory drive belt. The tensioner pulley can be serviced separately.

Scheme 1

1. Raise vehicle on hoist.
2. Remove belt splash shield (3). 1 - POWER STEERING PUMP 2 - ACCESSORY DRIVE BELT 3 - GENERATOR 4 - CRANKSHAFT PULLEY 5 - LOWER IDLER PULLEY 6 - CRANKSHAFT PULLEY 7 - WATER PUMP PULLEY 8 - ACCESSORY DRIVE BELT TENSIONER 9 - UPPER IDLER PULLEY
3. Remove accessory drive belt. Refer to «BELT, Serpentine, Removal»(ref-462462-S22037265562012040500000) .
4. Remove accessory drive belt tensioner mounting bolt. Remove accessory drive belt tensioner (8).

Scheme 2

1. Remove the accessory drive belt. Refer to «BELT, Serpentine, Removal»(ref-462462-S22037265562012040500000) .
2. Lower the vehicle.
3. Remove the tensioner bracket mounting bolts (1,2 3).
4. Raise and support the vehicle.
5. Remove the tensioner assembly (4) from underneath the vehicle.
6. If idler pulley is to be replaced, remove pulley from tensioner (4).

Scheme 3

1. Disconnect the negative battery cable.
2. Remove the water/power steering/vacuum pump assembly. Refer to «PUMP, Water, Removal»(ref-462462-S29831786742012040500000) .
3. Lower the vehicle.
4. Remove the coolant recovery bottle. Refer to «BOTTLE, Coolant Recovery, Removal»(ref-462462-S02887442662012040500000) .
5. Remove the charge air cooler.
6. Remove the A/C condenser. Refer to «CONDENSER, A/C, Removal»(ref-462505-S03949530382012040500000) .
7. Remove the A/C compressor. Refer to «COMPRESSOR, A/C, Removal»(ref-462505-S05879516482012040500000) .
8. Remove the generator. Refer to «GENERATOR, Removal»(ref-462468-S03491063682012040500000) .
9. Remove the EGR cooler. Refer to «COOLER, EGR, Removal»(ref-462462-S27203523532012040500000) .
10. Remove the accessory drive belt tensioner. Refer to «TENSIONER, Belt, Removal»(ref-462462-S38322152342012040500000) .
11. Remove the coolant bypass hose from the thermostat housing (2).
12. Remove the radiator hose (3) from the thermostat housing (2).
13. Remove the thermostat housing mounting bolts.
14. Remove the accessory drive bracket mounting bolts.
15. Remove the accessory drive bracket (1).
16. If necessary, separate the thermostat (2) from the accessory drive bracket (1).

The EGR cooler cools recirculated exhaust gasses to reduce combustion temperature which results in less NOx gases.

Scheme 4

Scheme 5

Scheme 6

Scheme 7

1. Disconnect the negative battery cable.
2. Remove engine cover.
3. Drain cooling system. Refer to «Standard Procedure»(ref-462462-S03285651472012040500000) .
4. Disconnect coolant hoses (1) from the EGR cooler (2).
5. Remove the upper EGR cooler bolt (1) and bracket (2).
6. Remove the A/C wiring connector bracket and position aside.
7. Remove the lower EGR cooler bolt (1). NOTE: Two bolts hidden under cooler.
8. Remove six bolts (1) and the EGR cooler (2).

Scheme 8

1. Clean all gasket mating surfaces.
2. Install a new gasket (1) onto the EGR body (2).
3. Install EGR cooler. Tighten bolts (1) to 9 N.m (80 in. lbs.).
4. Install the lower EGR cooler bolt (1). Tighten to 9 N.m (80 in. lbs.).
5. Install the A/C connector mounting bracket.
6. Install the upper EGR cooler bolt. Tighten bolt to 9 N.m (80 in. lbs.).
7. Connect coolant hoses (1) to the EGR cooler (2).
8. Fill cooling system Refer to «Standard Procedure»(ref-462462-S03285651472012040500000) .
9. Install engine cover.
10. Connect the negative battery cable.

Scheme 9

Note. It is not necessary to remove draincock during a routine coolant drain.

1. Remove the front passenger side wheel
2. Remove the front passenger side splash shield assembly from the wheelhouse Refer to «SHIELD, Splash, Front Wheel House, Removal»(ref-462504-S01107315142012040500000) .
3. Drain the cooling system. Refer to «Standard Procedure»(ref-462462-S03285651472012040500000) .
4. Open the draincock (2) by turning it counterclockwise until it stops.
5. Turn the draincock (2) back (clockwise) 1/8 turn.
6. Pull the draincock (2) from the radiator tank (1).

The radiator cooling fans are dual-speed electric motor driven fans. The radiator fan assembly includes two electric motors, two five blade fans, and a support shroud that is attached to the radiator. The radiator fans are serviced as an assembly.

The radiator is a cross-flow type (horizontal tubes) with design features that provide greater strength, as well as sufficient heat transfer capabilities to keep the engine coolant within operating temperatures.

The radiator has an aluminum core with plastic tanks. Although stronger than brass, plastic tanks are subject to damage by impact. Always handle radiator with care.

OPERATION

The radiator functions as a heat exchanger, using air flow across the exterior of the radiator tubes. This heat is then transferred from the coolant and into the passing air.

Scheme 10

1. Drain cooling system. Refer to «Standard Procedure»(ref-462462-S03285651472012040500000) .
2. Remove radiator fan. Refer to «FAN, Cooling, Removal»(ref-462462-S39272801822012040500000) .
3. Disconnect lower radiator hose.
4. Remove fasteners attaching AC condenser to radiator. Reposition AC condenser.
5. Remove radiator assembly by lifting it up from the engine compartment. Care should be taken not to damage the cooling fins and tubes during removal.

The ECT sensor provides an input to the PCM. As temperature increases, resistance of the sensor decreases. As coolant temperature varies, the ECT sensor resistance changes resulting in a different voltage value at the PCM ECT sensor signal circuit. The ECT sensor provides input for various PCM operations. The PCM uses the input to control air-fuel mixture, timing, and radiator fan on/off times.

When the Engine is cold and both the primary and secondary thermostats are closed. The coolant will circulate through the engine, heater system, and the bypass. The cooling system has no flow through the radiator

As the engine warms up, the primary thermostat will start to open at 82 °C (179 °F). Coolant will start to flow through the radiator oil cooler and transmission cooler. Coolant will flow through the transmission oil cooler only when the primary thermostat is fully open. The primary thermostat will fully open at 95 °C (203 °F).

The secondary thermostat will start to open at 95 °C (203 °F). This will increase the coolant flow through the cylinder block and cylinder head and the radiator. The secondary thermostat will fully open at 110 °C (230 °F).

If the thermostat is stuck open or allows coolant leakage through it, the engine will not operate at the proper temperature for obtaining engine fuel efficiency, performance and emissions levels. If this condition occurs, a diagnostic trouble code will be set and a MIL light will be turned on. Refer to the Powertrain Diagnostic Procedures for further information and diagnostics provided.