2003 FORD MUSTANG engine

GENERAL PROCEDURES
Piston —
to Cylinder Bore Clearance
1. Subtract the piston diameter from the cylinder bore diameter to find the piston- to-cylinder bore
clearance.
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GENERAL PROCEDURES
Piston —
Selection
NOTE: The cylinder bore must be within the specifications for taper and out-of- round before fitting a
piston.
1. Select a piston size based on the cylinder bore.
2. NOTE: For precision fit, new pistons are divided into three categories within each size range
based on their relative position within the range. A paint spot on the new pistons indicates the
position within the size range.
Choose the piston with the correct paint color.
zRefer to the appropriate section in Group 303 for the procedure.
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GENERAL PROCEDURES
Piston —
Ring End Gap
CAUTION: Use care when fitting piston rings to avoid possible damage to the piston ring
or the cylinder bore.
CAUTION: Piston rings should not be transferred from one piston to another.
NOTE: Cylinder bore must be within specification for taper and out-of- round.
1. Use a piston without rings to push a piston ring in a cylinder to the bottom of ring travel.
2. Use a feeler gauge to measure the top piston ring end gap and the second piston ring end gap. zRefer to the appropriate section in Group 303 for the procedure.
SECTION 303-
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GENERAL PROCEDURES
Piston —
Ring-to-Groove Clearance
1. Inspect the piston for ring land damage or accelerated wear.
2. Measure the piston ring- to-groove clearance.
z Refer to the appropriate section in Group 303 for the procedure.
z If out of specification, install new components as necessary. Refer to the appropriate
section in Group 303 for the procedure.
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GENERAL PROCEDURES
Piston —
Pin Diameter
1. Measure the piston pin diameter in two directions at the points shown. Verify the diameter is within specification.
zRefer to the appropriate section in Group 303 for the procedure.
z If out of specification, install new components as necessary. Refer to the appropriate
section in Group 303 for the procedure.
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GENERAL PROCEDURES
Connecting Rod —
Cleaning
CAUTION: Do not use a caustic cleaning solution or damage to connecting rods can
occur.
1. NOTE: The connecting rod large end is a matched set. The connecting rod cap must be
installed on the original connecting rod in the original position. Do not reverse the cap. Parts are
not interchangeable.
Mark and separate the parts and clean with solvent. Clean the oil passages.
SECTION 303-
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GENERAL PROCEDURES
Connecting Rod —
Large End Bore
1. Tighten the bolts to specification, then measure the bore in two directions. The difference is the connecting rod bore out-of-round. Verify the out-of- round is within specification.
z Refer to the appropriate section in Group 303 for the procedure.
z If out of specification, install new components as necessary. Refer to the appropriate
section in Group 303 for the procedure.
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GENERAL PROCEDURES
Connecting Rod —
Bushing Diameter
1. Measure the inner diameter of the connecting rod bushing, if equipped. Verify the diameter is within specification.
zRefer to the appropriate section in Group 303 for the procedure.
z If out of specification, install new components as necessary. Refer to the appropriate
section in Group 303 for the procedure.
SECTION 303-
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12003 Mustang Workshop Manual
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