Dodge Nitro. Manual — part 85

Cylinder Compression Pressure Test. See DIAGNOSIS AND TESTING. An engine cylinder head gasket
leaking between adjacent cylinders will result in approximately a 50-70% reduction in compression pressure.

CYLINDER-TO-WATER JACKET LEAKAGE TEST

VISUAL TEST METHOD

With the engine cool, remove the coolant pressure cap. Start the engine and allow it to warm up until thermostat
opens.

If a large combustion/compression pressure leak exists, bubbles will be visible in the coolant.

COOLING SYSTEM TESTER METHOD

Install Cooling System Tester 7700 or equivalent to pressure cap neck. Start the engine and observe the tester's
pressure gauge. If gauge pulsates with every power stroke of a cylinder a combustion pressure leak is evident.

CHEMICAL TEST METHOD

Combustion leaks into the cooling system can also be checked by using Bloc-Chek Kit C-3685-A or equivalent.
Perform test following the procedures supplied with the tool kit.

REMOVAL

CYLINDER HEAD - REMOVAL

RIGHT CYLINDER HEAD

WARNING:

USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING WITH
COOLANT PRESSURE CAP REMOVED.

WARNING:

WITH COOLING SYSTEM TESTER IN PLACE, PRESSURE WILL BUILD UP
FAST. EXCESSIVE PRESSURE BUILT UP, BY CONTINUOUS ENGINE
OPERATION, MUST BE RELEASED TO A SAFE PRESSURE POINT.
NEVER PERMIT PRESSURE TO EXCEED 138 kPa (20 psi).

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro

Fig. 76: Accessory Drive Belt Routing
Courtesy of CHRYSLER LLC

1. Perform the fuel relief procedure.

2. Disconnect the negative battery cable.

3. Drain cooling system. Refer to STANDARD PROCEDURE .

4. Remove the upper intake manifold. See REMOVAL.

5. Remove the lower intake manifold. See REMOVAL.

6. Remove accessory drive belt (7).

7. Remove accessory drive belt idler pulley.

1 - GENERATOR
2 - IDLER PULLEY
3 - WATER PUMP PULLEY
4 - CRANKSHAFT PULLEY
5 - ACCESSORY DRIVE BELT TENSIONER
6 - A/C COMPRESSOR
7 - ACCESSORY DRIVE BELT

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro

Fig. 77: Removing Power Steering Mounting Bolts, Pump & Crankshaft Damper
Courtesy of CHRYSLER LLC

8. Remove the power steering mounting bolts (3) and set the pump aside (Refer to REMOVAL ).

9. Remove crankshaft damper (4) (Refer to REMOVAL ).

Fig. 78: Removing/Installing Accessory Drive Bracket
Courtesy of CHRYSLER LLC

10. Remove the accessory drive bracket (2).

11. Remove the outer timing belt cover bolts and cover.

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro

Fig. 79: Removing/Installing Exhaust Pipe
Courtesy of CHRYSLER LLC

12. Remove front exhaust pipe to exhaust manifold mounting bolts (3,5).

13. Disconnect both oxygen sensor harness connectors on each side.

Fig. 80: Identifying Timing Gear Components
Courtesy of CHRYSLER LLC

1 - RIGHT CAMSHAFT
GEAR ALIGNMENT MARK

7 - LEFT CAMSHAFT
GEAR

2 - RIGHT CAMSHAFT

8 - LEFT CAMSHAFT

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro