2003 FORD MUSTANG oil viscosity

z
intake manifold gaskets
z cylinder head gaskets
z oil bypass filter
z oil filter adapter
z engine front cover
z oil filter adapter and filter body
z oil level indicator tube connection
z oil pressure sensor
Leakage Points— Under Engine—With Vehicle on Hoist
z oil pan gaskets (6710)
z oil pan sealer
z oil pan rear seal (6723)
z engine front cover gasket
z crankshaft front seal (6700)
z crankshaft rear oil seal (6701)
z crankshaft main bearing cap side bolts
z oil filter adapter and filter body
z oil cooler, if equipped
Leakage Points— With Transmission and Flywheel Removed
z crankshaft rear oil seal
z rear main bearing cap parting line
z rear main bearing cap and seals
z flywheel mounting bolt holes (with flywheel [6375] installed)
z camshaft rear bearing covers (6266) or pipe plugs at the end of oil passages
Oil leaks at crimped seams in sheet metal parts and cracks in cast or stamped parts can be detected
when using the dye method.
Compression Test— Compression Gauge Check
1. Make sure the oil in the crankcase is of the correct viscosity and at the correct level and that the battery (10655) is correctly charged. Operate the vehicle until the engine is at normal operating
temperature. Turn the ignition switch to the OFF position, then remove all the spark plugs
(12405).
2. Set the throttle plates in the wide- open position.
3. Install a compression gauge such as the Compression Tester in the No. 1 cylinder.
4. Install an auxiliary starter switch in the starting circuit. With the ignition switch in the OFF position, and using the auxiliary starter switch, crank the engine a minimum of five compression
strokes and record the highest reading. Note the approximate number of compression strokes Klj . 7 ba
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Engines need oil to lubricate the following internal components:
zcylinder block cylinder walls
z pistons and piston, pin and rings (6102)
z intake and exhaust valve stems
z intake and exhaust valve guides
z all internal engine components
When the pistons move downward, a thin film of oil is left on the cylinder walls. As the vehicle is
operated, some oil is also drawn into the combustion chambers past the intake and exhaust valve
stem seals and burned.
The following is a partial list of conditions that can affect oil consumption rates:
zengine duty cycle
z operator driving habits
z ambient temperature
z quality and viscosity of the oil
Operation under varying conditions can frequently be misleading. A vehicle that has been run for
several thousand miles on short trips or in below- freezing ambient temperatures may have consumed
a "normal" amount of oil. However, when checking the engine oil level, it may measure up to the FULL
or MAX on the oil level dipstick due to dilution (condensation and fuel) in the engine crankcase. The
vehicle might then be driven at high speeds on the highway where the condensation and fuel boil off.
The next time the engine oil is checked, it may appear that a liter (quart) of oil was used in about 160
km (100 miles). This perceived 160 km (100 miles) per liter (quart) oil consumption rate causes
customer concern even though the actual overall oil consumption rate is about 2,400 km (1,500 miles)
per liter (quart).
Make sure the selected engine oil meets the current recommended API performance category with
SAE viscosity grade as shown in the vehicle Owner's Guide. It is also important that the engine oil is
changed at the intervals specified. Refer to the vehicle Owner's Guide.
Oil Pressure Test
1. Disconnect and remove the oil pressure sensor (9278) from the engine.
2. Connect the Oil Pressure Gauge to the oil pressure sender oil galley port.
3. Run the engine until normal operating temperature is reached.
4. Run the engine at the specified rpm and record the gauge reading.
5. The oil pressure should be within specifications; refer to the specification chart in the appropriate engine section.
6. If the pressure is not within specification, check the following possible sources: zinsufficient oil
z oil leakage
z worn or damaged oil pump
z oil pump screen cover and tube (6622)
z excessive main bearing clearance Klj . 13 ba
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z
The inner rotor is piloted on the crankshaft post and is driven through flats on the crankshaft.
z System pressure is limited by an integral, internally- vented relief valve which directs the
bypassed oil back to the inlet side of the oil pump.
z Oil pump displacement has been selected to provide adequate volume to ensure correct oil
pressure both at hot idle and maximum speed.
z The relief valve calibration protects the system from excessive pressure during high viscosity
conditions.
z The relief valve is designed to provide adequate connecting rod bearing lubrication under high-
temperature and high- speed conditions.
Cooling System
The engine cooling system includes the following:
zradiator
z water pump
z the electric cooling fan motor and fan blade, activated by the variable control module
z the degas bottle, which aids in maintaining the correct volume of engine coolant
z water thermostat
z upper radiator hose
z lower radiator hose
z heater water hoses
Drive Belt System
The 4.6L (4V) DOHC engine is equipped with a serpentine drive belt. To ensure maximum life, a
replacement drive belt should be of the same type as originally installed.
zThe accessories mounted on the front of the engine are belt- driven by the crankshaft.
z The serpentine drive belt is routed over each accessory pulley, driven by the crankshaft pulley
bolted to the crankshaft.
For service procedures, including tensioning, refer to Section 303 - 05 . Klj . 3 ba
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z
System pressure is limited by an integral, internally- vented relief valve which directs the
bypassed oil back to the inlet side of the oil pump.
z Oil pump displacement has been selected to provide adequate volume to ensure correct oil
pressure both at hot idle and maximum speed.
z The relief valve calibration protects the system from excessive pressure during high viscosity
conditions.
z The relief valve is designed to provide adequate connecting rod bearing lubrication under high-
temperature and high- speed conditions.
Cooling System
The engine cooling system includes the following:
zradiator
z coolant pump
z the electric cooling fan motor and fan blade, activated by the variable control module
z the degas bottle, which aids in maintaining the correct volume of engine coolant
z thermostat
z upper radiator hose
z lower radiator hose
z heater coolant hoses
Drive Belt System
The 4.6L (4V) DOHC engine is equipped with a serpentine drive belt. To ensure maximum life, a
replacement drive belt should be of the same type as originally installed.
zThe accessories mounted on the front of the engine are belt- driven by the crankshaft.
z The serpentine drive belt is routed over each accessory pulley, driven by the crankshaft pulley
bolted to the crankshaft. For service procedures, including tensioning, refer to Section 303 - 05 . Klj . 3 ba
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z
A one- piece lip- type seal (installed from the front of the A/C compressor) is used to seal it at the
shaft opening in the assembly.
z Five double- acting pistons operate within the cylinder assembly. The pistons are actuated by a
swashplate that converts the rotating action of the shaft to a reciprocating force.
z Reed- type discharge valves are located between the cylinder assembly and the head at each
end of the A/C compressor.
z The A/C compressor uses PAG oil, or equivalent. This oil contains special additives required for
the A/C compressor.
z The A/C compressor oil from vehicles equipped with an FS- 10 A/C compressor may have some
dark colored streaking while maintaining a normal oil viscosity. This is normal for the A/C
compressor and is caused by break- in wear of the piston rings.
The magnetic A/C clutch has the following characteristics: zIt drives the compressor shaft.
z When the battery positive voltage (B+) is applied to the A/C clutch field coil, the clutch plate and
hub assembly is drawn toward the A/C clutch pulley.
z The magnetic force locks the clutch plate and hub assembly and the A/C clutch pulley together
as one unit, causing the compressor shaft to rotate.
z When (B+) is removed from the A/C clutch field coil, springs in the clutch plate and hub
assembly move the clutch plate away from the A/C clutch pulley. A/C Compressor Pressure Relief Valve Item Part Number Description
1 19D798 A/C clutch field coil
2 19D784 A/C clutch pulley
3 N805338-S2 Pulley snap ring
4 19D648 A/C clutch hub spacer
5 19D786 Disk and hub assembly
6 N805332-S2 A/C clutch bolt Klj . 3 ba
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