Dodge dakota 2002 Service Manual page 1492

DR
CYLINDER HEAD
DESCRIPTION
DESCRIPTION—CYLINDER HEAD
The cast iron cylinder heads (Fig. 6) are mounted
to the cylinder block using ten bolts. The spark plugs
are located in the peak of the wedge between the
valves.
Fig. 6 Cylinder Head Assembly—V-8 Gas Engines
1 - EXHAUST VALVE
2 - SPARK PLUGS
3 - EXHAUST VALVES
4 - SPARK PLUGS
5 - EXHAUST VALVE
6 - INTAKE VALVES
7 - INTAKE VALVES
DESCRIPTION - CYLINDER HEAD COVER
GASKET
The cylinder head cover gasket (Fig. 7) is a steel-
backed silicone gasket, designed for long life usage.
Fig. 7 Cylinder Head Cover Gasket V-8 Gas Engines
1 - CYLINDER HEAD COVER GASKET
OPERATION
OPERATION—CYLINDER HEAD
The cylinder head closes the combustion chamber
allowing the pistons to compress the air fuel mixture
to the correct ratio for ignition. The valves located in
the cylinder head open and close to either allow clean
air into the combustion chamber or to allow the
exhaust gases out, depending on the stroke of the
engine.
OPERATION - CYLINDER HEAD COVER
GASKET
The steel-backed silicone gasket is designed to seal
the cylinder head cover for long periods of time
through extensive heat and cold, without failure. The
gasket is designed to be reusable.
DIAGNOSIS AND TESTING—CYLINDER HEAD
GASKET FAILURE
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
• Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
− Loss of engine power
− Engine misfiring
− Poor fuel economy
• Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
− Engine overheating
− Loss of coolant
− Excessive steam (white smoke) emitting from
exhaust
− Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test in this
section. An engine cylinder head gasket leaking
between adjacent cylinders will result in approxi-
mately a 50–70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
ENGINE - 5.9L 9 - 243