Dodge ram truck 3500 1996 Service Manual page 993

B R
ENGINE 1 - 3
GENERAL INFORMATION (Continued)
ing is the recommended procedure for the use of
Plastigage:
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) The total clearance of the main bearings can be
determined only by removing the weight of the
crankshaft. This can be accomplished by either of two
methods:
METHOD -1 (PREFERRED)
Shim the bearings adjacent to the bearing to be
checked. This' will remove the clearance between
upper bearing shell and the- crankshaft. Place a min­
imum of 0.254 mm (0.010 in.) shim between the bear­
ing shell and the adjacent bearing cap. Tighten the
bolts to 18 N-m (13 ft. lbs.) torque.
• C H E C K NO. 1 BEARING: Shim No. 2 main
bearing.
• C H E C K NO* 2 BEAMING: Shim No. 1 and No.
3 main bearing.
• C H E C K NO. 3 BEAMING: Shim No. 2 and No.
4 main bearing.
• C H E C K NO* .4 BEARING: Shim No. 3 main
bearing (3.9L). Shim No. 3 and No. 5 main bearing
(5.2L, 5.9L, 8.0L and 5.9L-Diesel).
• C H E C K M M BEARING: Shim No. 4 main
bearing (5.2L and 5.9L). Shim No. 4 and No. 6 main
bearing (8.0L and 5.9L-Diesel).
• C H E C K NO* 6 BEARING: Shim No. 5 main
bearing (8.0L). Shim No. 5 and No. 7 main bearing
(5.9L-Diesel). -
• C H E C K NO. 7 BEARING: Shim No. 6 main
bearing (5.9L-Diesel).
NOTE; Remove ail shims before assembling
engine,
METHOD - 2 (ALTERNATIVE)
Support the weight of the crankshaft with a jack
placed under the counterweight adjacent to the bear­
ing being checked.
(1) Place a piece of Plastigage across the entire
width of the bearing cap shell (Fig. 1). Position the
Plastigage approximately 6.35 mm (1/4 in.) off center
and away from the oil holes. In addition, suspect
areas can be checked by placing the Plastigage in
that area. Tighten the bearing cap bolts of the bear­
ing being checked to 115 N-m (85 ft. lbs.) torque. DO
NOT rotate the crankshaft or the Plastigage
may be smeared, giving inaccurate results.
(2) Remove the bearing cap and compare the width
of the flattened Plastigage with the scale provided on
the package (Fig. 2). Plastigage generally comes in
two scales (one scale is in inches and the other is a
metric scale). Locate the band closest to the same
width. This band shows the amount of clearance. Dif-
Fig. 1 Placement of Plastigage in Bearing Shell
ferences in readings between the ends indicate the
amount of taper present. Record all readings taken.
Refer to Engine Specifications.
RN861
Fig. 2 Clearance Measurement
(3) Plastigage is available in a variety of clearance
ranges. The 0.025-0.076 mm (0.001-0.003 in.) range
is usually the most appropriate for checking engine
bearing clearances.
coMMEcnmm moo B E A R I M G C L E A R A N C E
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:
(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 cap shell (Fig. 1). Position the
Plastigage approximately 6.35 mm (1/4 inch) off cen­
ter and away from the oil holes. In addition, suspect
areas can be checked by placing the Plastigage in the
suspect area.
(3) The crankshaft must be rotated until the con­
necting rod to be checked starts moving toward the
top of the engine. Only then should the rod cap, with
Plastigage in place, be assembled. Tighten the rod
cap nut to 61 N-m (45 ft. lbs.) torque. DO NOT
rotate the crankshaft or the Plastigage may be
smeared, giving inaccurate results.
(4) Remove the bearing cap and compare the width
of the flattened Plastigage with the scale provided on