(2) Necking can be checked by holding a scale or
straight edge against the threads. If all the threads
do not contact the scale the bolt should be replaced.
(3) Before installing the bolts, lubricate the
threads with engine oil.
(4) Install bolts finger tight then alternately
torque each nut to assemble the cap properly.
(5) Tighten the nuts to 27 N·m PLUS 1/4 turn (20
ft. lbs. PLUS 1/4 turn).
(6) Mount a dial indicator to a stationary point on
engine. Locate probe perpendicular to and resting
against the connecting rod cap being checked. Move
connecting rod all the way to rear of its travel. Zero
the dial indicator. Move connecting rod forward to
limit of travel and read the dial indicator (Fig. 28).
Refer to Engine Specifications. Repeat procedure for
each connecting rod. Turn crankshaft for connecting
rod accessibility.
CRANKSHAFT MAIN BEARING—FITTING
The main bearings are “select fit” to achieve proper
oil clearances. For main bearing selection, the block
and crankshaft have grade identification marks.
The grade marks for the cylinder block main bear-
ing bore grade is located on the pan rail just below
the left side engine mount bracket (Fig. 30). These
marks are read left to right, corresponding to main
bore 1, 2, 3, 4.
The grade marks for the crankshaft are located on
the rearmost crankshaft counter weight as shown in
(Fig. 29). The crankshaft journal grade marks are
read left to right, corresponding with journal number
1, 2, 3, 4.
Use the Main Bearing Selection Chart to properly
select the main bearings. For an example, if the main
bore grade is 3 and the journal grade is 2, the proper
select fit bearing would be (2) +0.003 mm (+0.0002
in.).
NOTE: Service main bearings have a number from
1 – 5 marked in ink on the bearing surface (Fig. 31).
For verification, use the Main Bearing Selection
Chart for number to size identification.
The upper main bearing has a oil feed hole and a
center groove to allow lubrication of the main journal
and must be properly positioned in the block.
NOTE: Although cylinder bores are graded for size,
there is only one piston size.
Fig. 26 Checking Connecting Rod Bearing
Clearance—Typical
Fig. 27 Check for Stretched Bolts
1 – STRETCHED BOLT
2 – THREADS ARE NOT STRAIGHT ON LINE
3 – THREADS ARE STRAIGHT ON LINE
4 – UNSTRETCHED BOLT
Fig. 28 Connecting Rod Side Clearance Measuring
9 - 26 2.7L ENGINE LH
SERVICE PROCEDURES (Continued)
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