2003 FORD MUSTANG engine

4. Inspect for normal burning.
zCheck for light tan or gray deposits on the firing tip.
5. Inspect for pre- ignition, identified by melted electrodes and a possibly damaged insulator.
Metallic deposits on the insulator indicate engine damage. This may be caused by incorrect
ignition timing, wrong type of fuel or the unauthorized installation of a heli- coil insert in place of
the spark plug threads.
zInstall a new spark plug.
6. Inspect for overheating, identified by a white or light gray spots and with bluish- burnt
appearance of electrodes. This is caused by engine overheating, wrong type of fuel, loose spark
plugs, spark plugs with an incorrect heat range, low fuel pump pressure or incorrect ignition
timing.
zInstall a new spark plug. Klj . 2 ba
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GENERAL PROCEDURES
Exhaust Manifold —
Inspection
1. Place a straight edge across the exhaust manifold flanges and check for warping with a feeler gauge.
SECTION 303-
00: Engine System — General Information 2003 Mustang Workshop Manual Special Tool(s)
Straight Edge
303-
D039 (D83L-4201- A) or
equivalent Klj . 1 ba
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GENERAL PROCEDURES
Bearing —
Inspection
1. Inspect bearings for the following defects. Possible causes are shown: 1. Cratering — fatigue failure.
2. Spot polishing — incorrect seating.
3. Imbedded dirt engine oil.
4. Scratching — dirty engine oil.
5. Base exposed — poor lubrication.
6. Both edges worn — journal damaged.
7. One edge worn — journal tapered or bearing not seated.
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00: Engine System — General Information 2003 Mustang Workshop Manual Klj . 1 ba
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SPECIFICATIONS
SECTION 303-
01A: Engine — 3.8L 2003 Mustang Workshop Manual General Specifications
Item Specification
Lubricants and Sealants
SAE 5W-
20 Premium Synthetic Blend Motor Oil
XO- 5W20- QSP WSS-
M2C153- H Gasket and Trim Adhesive F3AZ-19B508-
AA ESE-
M2G52- A Pipe Sealant with Teflon® D8AZ-19554-
A WSK-
M2G350- A2 Silicone Gasket and Sealant F7AZ-19554-
EA WSE-
M4G323- A4 Metal Surface Cleaner F4AZ-19A536-
RA WSE-
M5B392- A Engine
Displacement 3.8L
Number of cylinders 6
Bore 96.8325 mm (3.81 in)
Stroke 86.0 mm (3.39 in)
Firing order 1-4-2-5-3-
6 Oil pressure (hot 2,500 rpm) 40-
125 psi Oil capacity 5 quarts w/filter change
Compression ratio —
Cylinder Head and Valve Train
Cylinder head gasket surface flatness 0.18 mm (0.007 in)
Combustion chamber volume 61.5-
64.5 cc Valve arrangement (front to rear) —
Valve guide bore diameter 7.015-
7.044 mm (0.276- 0.277 in) Valve stem diameter —
intake 6.955-
6.988 mm (0.2738- 0.2751 in) Valve stem diameter —
exhaust 6.929-
6.962 mm (0.2728- 0.2741 in) Valve stem diameter —
oversize (intake) 9.075-
9.055 mm (0.3573- 0.3565 in) Valve stem diameter —
oversize (exhaust) 9.063-
9.043 mm (0.3568- 0.3560 in) Valve stem diameter —
oversize (intake) 9.456-
9.436 mm (0.3723- 0.3715 in) Valve stem diameter —
oversize (exhaust) 9.444-
9.424 mm (0.3718- 0.3710 in) Valve stem-
to-guide clearance — intake 0.020-
0.069 mm (0.045- 0.090 in) Valve stem-
to-guide clearance — exhaust 0.038-
0.083 mm (0.0015- 0.0033 in) Valve head diameter —
intake 47.27 mm (1.86 in)
Valve head diameter —
exhaust 37.1 mm (1.46 in)
Valve face runout 0.05 mm (0.002 in)
Valve face angle 45.675 degrees
Valve seat width 1.5-
2.0 mm (0.06- 0.08 in) Valve seat runout (T.I.R.) 0.076 mm (0.003 in) Klj . 1 ba
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A/C compressor bracket-
to-cylinder head stud bolt 25 18 —
Oil level indicator tube-
to-cylinder head bolt 10 — 89
Coolant recovery reservoir bracket-to-
GOP bolts 9 — 80
Motor mount-
to-subframe nuts 115 85 —
Oil pan drain plug 26 19 —
Wire harness bracket to motor mount nut 27 20 —
Steering column pinch bolt 47 35 —
Front subframe-
to-body bolts 90 66 —
Front subframe-
to-shock tower bolts 115 85 —
Oil pan-to-
cylinder block bolts a — — —
Oil pan-to-
transmission bell housing 45 33 —
Main bearing bridge nuts 32 24
Oil pump cover-
to-engine front cover bolts 25 18 —
Oil pump cover-
to-engine front cover bolt 10 89 —
Oil pickup tube-
to-cylinder block bolts 25 18 —
Oil pickup tube-
to-oil pan baffle nut 48 35 —
Flywheel-
to-crankshaft bolts 80 59 —
Wire harness bracket-
to-motor mount stud- nut 27 20 —
Engine ground strap-
to-motor mount nut 27 20 —
Motor mount-
to-motor mount bracket bolts 70 52 —
RH motor mount-
to-motor mount bracket nut 70 52 —
Hood ground strap-
to-hood hinge bolt 12 9 —
Hood hinge nuts 12 9 —
Generator mounting bracket 25 18 —
Power steering pump bracket nuts 8 — 71
Power steering pump bolts 25 18 —
Valve tappet guide plate bolts 12 9 —
Generator positive cable nut 10 — 89
Power steering pressure tube to pump nut 40 30 —
Accelerator cable bracket-
to-intake manifold bolts 10 — 89
42-
pin connector bolt 10 — 89
Transmission oil cooler tube bracket-
to-motor mount bracket nut 27 20
Torque converter-
to-flywheel nuts 36 27 —
Engine-
to-transmission bolts 40 30 —
Engine mount bracket-
to-engine bolts 70 52 —
Engine mount bracket-
to-engine nuts 70 52 —
Water pump pulley bolts 25 18 —
Oil filter
b — — —
Upper intake manifold-
to-lower intake manifold bolts a — — —
Lower intake manifold-
to-cylinder head bolts a — — —
Rocker arm pivot-
to-cylinder head bolts a — — — Klj . 5 ba
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DESCRIPTION AND OPERATION
Engine
The 3.8L engine has:
za V- block with six cylinders and splayed crankpins.
z a distributorless ignition system.
z a multiport, sequential fuel injection (SFI) system.
z overhead valves.
z hydraulic valve tappets for automatic lash adjustment.
z connecting rod parting faces that are unique with an interference fit.
z an engine dynamic balance shaft.
SECTION 303-
01A: Engine — 3.8L 2003 Mustang Workshop Manual Klj . 1 ba
12003 Mustang Workshop Manual
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DESCRIPTION AND OPERATION
Engine Component View
Cylinder Heads and Valve Train Components
SECTION 303-
01A: Engine — 3.8L 2003 Mustang Workshop Manual Item Part Number Description
1 9D477 EGR valve-to-
exhaust manifold tube 2 6C342 Crankcase ventilation hose
3 6582 Valve cover —
RH 4 12405 Spark plug
5 6049 Cylinder head —
RH 6 6582 Valve cover —
LH 7 6766 Oil fill cap
8 6758 Crankcase ventilation tube Klj . 1 ba
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Engine Front Cover Components 9 6A666 Positive crankcase ventilation valve
10 6565 Push rod
11 6564 Rocker arm
12 6A528 Rocker arm seat
13 N807699 Bolt
14 6518 Valve spring retainer key
15 6514 Valve spring retainer
16 6513 Valve spring
17 6A517 Valve stem seal
18 611497 Bolt
19 6049 Cylinder head —
LH 20 9448 Exhaust manifold gasket —
LH 21 17A084 Engine lifting eye
22 6754 Oil level indicator tube
23 9430 Exhaust manifold —
LH 24 6507 Intake valve
25 6505 Exhaust valve
26 6051 Head gasket —
LH 27 6051 Head gasket —
RH 28 9448 Exhaust manifold gasket —
RH 29 9430 Exhaust manifold —
RH 30 17A084 Engine lifting eye Klj . 2 ba
82003 Mustang Workshop Manual
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