Chrysler neon 1997 Service Manual page 428

PL
FRONT MIDDLE OF BORE
DIAGNOSIS AND TESTING (Continued)
USE FOR
SIZING
PISTON
oil pick-up screen or a damaged oil pick-up tube
O-ring.
SERVICE PROCEDURES
CYLINDER BORE AND PISTON SIZING
The cylinder walls should be checked for out-of-
round and taper with Tool C-119 (Fig. 3). The cylin-
der bore out-of-round is 0.050 mm (.002 inch)
maximum and cylinder bore taper is 0.051 mm (0.002
inch) maximum. If the cylinder walls are badly
scuffed or scored, the cylinder block should be
rebored and honed, and new pistons and rings fitted.
Whatever type of boring equipment is used, boring
and honing operation should be closely coordinated
with the fitting of pistons and rings in order that
specified clearances may be maintained. Refer to
Honing Cylinder Bores outlined in the Stan-
dard Service Procedures for specification and
procedures.
Measure the cylinder bore at three levels in direc-
tions A and B (Fig. 3). Top measurement should be
10 mm (3/8 inch) down and bottom measurement
should be 10 mm (3/8 inch.) up from bottom of bore.
Refer to Cylinder Bore and Piston Specifications
Table.
Fig. 3 Checking Cylinder Bore Size
SIZING PISTONS
Piston and cylinder wall must be clean and dry.
Piston diameter should be measured 90 degrees to
piston pin about 17.5 mm (11/16 inch) from the bot-
tom of the skirt as shown in (Fig. 4). Cylinder bores
should be measured halfway down the cylinder bore
PISTON
CYLINDER BORE AND PISTON
SPECIFICATIONS TABLE
Standard Bore Maximum
Out-of-Round
87.5 mm (3.445 0.051 mm
in.) (0.002 in.)
Standard Piston Size
87.463 - 87.481 mm (3.4434 - 3.4441 in.)
Piston to Bore Clearance
0.012 - 0.044 mm (0.0004 - 0.0017 in.)
Measurements Taken at Piston Size Location
and transverse to the engine crankshaft center line
shown in (Fig. 3). Refer to Cylinder Bore and Speci-
fications Table. Correct piston to bore clearance must
be established in order to assure quiet and economi-
cal operation.
Fig. 4 Piston Measurements
Chrysler engines use pistons designed specifically
for each engine model. Clearance and sizing locations
vary with respect to engine model.
NOTE: Pistons and cylinder bores should be mea-
sured at normal room temperature, 21°C (70°F).
FITTING PISTON RINGS
(1) Wipe cylinder bore clean. Insert ring and push
down with piston to ensure it is square in bore. The
ring gap measurement must be made with the ring
positioning at least 12 mm (0.50 inch) from bottom of
cylinder bore. Check gap with feeler gauge (Fig. 5).
Refer to specifications (Fig. 7).
(2) Check piston ring to groove side clearance (Fig.
6). Refer to specification (Fig. 7).
FITTING CONNECTING RODS
(1) Follow the procedure specified in the Standard
Service Procedures Section for Measuring Main Bear-
ing Clearance and Connecting Rod Bearing Clear-
ance (Fig. 8). Refer to specifications.
2.0L SOHC ENGINE
O.D. MENT LOCATION MEASURE-
Maximum
Taper
0.051 mm
(0.002 in.)
9 - 15