Dodge Nitro. Manual — part 24

Fig. 72: Cylinder Head Bolt Tightening Sequence
Courtesy of CHRYSLER LLC

21. Remove the cylinder head retaining bolts. See Fig. 72.

CAUTION: Do not overlook the four smaller bolts at the front of the cylinder

head. Do not attempt to remove the cylinder head without removing
these four bolts.

CAUTION: Do not hold or pry on the camshaft target wheel for any reason. A

damaged target wheel can result in a vehicle no start condition.

* - INDICATES SEALANT ON THREADS

NOTE:

The cylinder head is attached to the cylinder block with twelve bolts.

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro

22. Remove the cylinder head and gasket. Discard the gasket.

CLEANING

CYLINDER HEADS

Fig. 73: Proper Tool Usage for Surface Preparation
Courtesy of CHRYSLER LLC

CAUTION: Do not lay the cylinder head on its gasket sealing surface, do to the design

of the cylinder head gasket any distortion to the cylinder head sealing
surface may prevent the gasket from properly sealing resulting in leaks.

1 - PLASTIC/WOOD SCRAPER

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro

To ensure engine gasket sealing, proper surface preparation must be performed, especially with the use of
aluminum engine components. See Fig. 73. See STANDARD PROCEDURE.

INSPECTION

CYLINDER HEADS

1. Inspect the cylinder head for out-of-flatness, using a straightedge and a feeler gauge. If measurements

exceed 0.0508 mm (0.002 in.) replace the cylinder head.

2. Inspect the valve seats for damage. Service the valve seats as necessary.

3. Inspect the valve guides for wear, cracks or looseness. If either condition exist, replace the cylinder head.

INSTALLATION

CYLINDER HEAD - RIGHT

Fig. 74: Stretched Bolt, Threads Are Not Straight On Line, Threads Are Straight On Line & Unstreched
Bolt
Courtesy of CHRYSLER LLC

NOTE:

The cylinder head bolts are tightened using a torque plus angle procedure. The
bolts must be examined BEFORE reuse. If the threads are necked down (2) the
bolts should be replaced.

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro

Necking can be checked by holding a straight edge against the threads. If all the threads do not contact the scale,
the bolt should be replaced. See Fig. 74.

Fig. 75: Proper Tool Usage for Surface Preparation
Courtesy of CHRYSLER LLC

1. Clean the cylinder head and cylinder block mating surfaces. See Fig. 75.

1 - PLASTIC/WOOD SCRAPER

CAUTION: When cleaning cylinder head and cylinder block surfaces, DO NOT use a

metal scraper because the surfaces could be cut or ground. Use only a
wooden or plastic scraper (1).

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro