Chrysler 1997 Stratus Convertible RHD Service Manual page 740

9 - 4 ENGINE
GENERAL INFORMATION (Continued)
MEASURING MAIN BEARING AND CONNECTING
ROD BEARING CLEARANCES
Fig. 3 Plastigage Placed in Lower Shell
PLASTIGAGE METHOD
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The follow-
ing is the recommended procedure for the use of
Plastigage:
NOTE: The total clearance of the main bearings
can only be determined by removing the weight of
the crankshaft. This can be accomplished by either
of two methods:
PREFERRED METHOD
Shimming the bearings adjacent to the bearing to
be checked in order to remove the clearance between
upper bearing shell and the crankshaft. This can be
accomplished by placing a minimum of 0.254 mm
(0.010 in.) shim (e. g. cardboard, matchbook cover,
etc.) between the bearing shell and the bearing cap
on the adjacent bearings and tightening bolts to
14-20 N·m (10-15 ft. lbs.). The number of main bear-
ing will vary from engine to engine.
ENGINE WITH 5 MAIN BEARINGS
• When checking #1 main bearing shim #2 main
bearing.
• When checking #2 main bearing shim #1 & 3
main bearing.
• When checking #3 main bearing shim #2 & 4
main bearing.
• When checking #4 main bearing shim #3 & 5
main bearing.
• When checking #5 main bearing shim #4 main
bearing.
ENGINE WITH 4 MAIN BEARING
• When checking #1 main bearing shim # 2 main
bearing.
• When checking #2 main bearing shim #1 & #3
main bearing.
PLASTIGAGE
• When checking #3 main bearing shim #2 & #4
main bearing.
• When checking #4 main bearing shim #3 main
bearing.
NOTE: REMOVE ALL SHIMS BEFORE REASSEM-
BLING ENGINE
ALTERNATIVE METHOD
The weight of the crankshaft can be supported by a
jack under the counterweight adjacent to the bearing
being checked.
PLASTIGAGE PROCEDURE
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 in.) off center and away from the oil
holes (Fig. 3). (In addition, suspected areas can be
checked by placing the Plastigage in the suspected
area). Torque the bearing cap bolts of the bearing
being checked to the proper specifications.
(3)
width of the flattened Plastigage (Fig. 4) with the
metric scale provided on the package. Locate the
band closest to the same width. This band shows the
amount of clearance in thousandths of a millimeter.
Differences in readings between the ends indicate the
amount of taper present. Record all readings taken.
Refer to Engine Specifications. Plastigage gener-
ally is accompanied by two scales. One scale is
in inches, the other is a metric scale.
NOTE: Plastigage is available in a variety of clear-
ance ranges. Use the most appropriate range for
the specifications you are checking.
CONNECTING ROD BEARING CLEARANCE
Engine connecting rod bearing clearances can be
determined by use of Plastigage or equivalent. The
following is the recommended procedure for the use
of Plastigage:
Fig. 4 Clearance Measurement
Remove the bearing cap and compare the
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