Dodge Nitro. Manual — part 35

5. Apply a 2.5mm (0.100 inch) bead of Mopar® Engine RTV sealant to the cylinder block-to-bedplate

mating surface (2,3) as shown.

Fig. 103: Bedplate Tightening Sequence
Courtesy of CHRYSLER LLC

6. Coat the crankshaft main bearing journals with clean engine oil and position the bedplate onto the

cylinder block.

7. Install the bedplate retaining bolts, making sure to place the stud bolts in the correct location, Tighten the

bolts in the sequence shown.

Hand tighten bolts 1D,1G and 1F until the bedplate contacts the block.

Tighten bolts 1A - 1J to 54 N.m (40 ft. lbs.)

Tighten bolts 1 - 8 to 7 N.m (5 ft. lbs.)

Turn bolts 1 - 8 an additional 90°.

Tighten bolts A - E 27 N.m (20 ft. lbs.).

NOTE:

Make sure that the bedplate and cylinder block sealing surfaces are clean
and free of oil or other contaminants. Contaminants on the sealing
surfaces may cause main bearing distortion and/or oil leaks.

NOTE:

Lubricate the bedplate retaining bolts with clean engine oil prior to
installation.

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro

8. Measure crankshaft end play.

9. Install the connecting rods and measure side clearance. See STANDARD PROCEDURE.

10. Install oil pump. See INSTALLATION.

11. Install the engine. See INSTALLATION.

BEARINGS-CRANKSHAFT MAIN

STANDARD PROCEDURE

CRANKSHAFT MAIN BEARINGS

SELECT FIT IDENTIFICATION

Fig. 104: Rearmost Crankshaft Counter Weight, Target Wheel & Main Bearing Select Fit Markings
Courtesy of CHRYSLER LLC

1 - REARMOST CRANKSHAFT COUNTER WEIGHT

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro

The main bearings are "select fit" to achieve proper oil clearances. For main bearing selection, the crankshaft
position sensor target wheel (2) has grade identification marks stamped into it. These marks are read from left to
right, corresponding with journal number 1, 2, 3, 4. The crankshaft position sensor target wheel is mounted to
the number 6 counter weight (1) on the crankshaft. See Fig. 104.

INSPECTION

Wipe the inserts clean and inspect for abnormal wear patterns and for metal or other foreign material imbedded
in the lining. Normal main bearing insert wear patterns are illustrated.

Inspect the back of the inserts for fractures, scrapings or irregular wear patterns.

Inspect the upper insert locking tabs for damage.

Replace all damaged or worn bearing inserts.

MAIN BEARING JOURNAL DIAMETER (CRANKSHAFT REMOVED)

Remove the crankshaft from the cylinder block. See REMOVAL.

Clean the oil off the main bearing journal.

Determine the maximum diameter of the journal with a micrometer. Measure at two locations 90° apart at each
end of the journal.

The maximum allowable taper is 0.008mm (0.0004 inch.) and maximum out of round is 0.005mm (0.002 inch).
Compare the measured diameter with the journal diameter specification (Main Bearing Fitting Chart). Select
inserts required to obtain the specified bearing-to-journal clearance.

Install the crankshaft into the cylinder block. See INSPECTION.

Check crankshaft end play.

CRANKSHAFT MAIN BEARING SELECTION

2 - TARGET WHEEL
3 - MAIN BEARING SELECT FIT MARKINGS

Crankshaft Marking

JOURNAL SIZE

SIZE mm (in.)

"R" Size

63.488 - 63.496 mm
(2.4995 - 2.4998 in.)

"S" Size

63.496 - 63.500 mm (2.4998 - 2.4999 in.)

"T" Size

63.500 - 63.504 mm (2.4999 - 2.501 in.)

"U" Size

63.504 - 63.512 mm (2.5001 - 2.5004 in.)

Bearing size

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro

1. Service main bearings are available in four grades. The chart identifies the four service grades available.

SEAL-CRANKSHAFT OIL-FRONT

REMOVAL

CRANKSHAFT OIL SEAL - FRONT

Bearing Code

Size

Application

Upper Bearing

A

.2.443 - 2.447 mm

Use with crankshaft size "R"

(.0961 -.0963 in.)

-

B

2.439 - 2.443 mm

Use with crankshaft "S, T"

(0.960 -.0961 in.)

-

C

2.435 - 2.439 mm

Use with crankshaft "U"

(.0958 -.0960 in.)

-

Lower Bearing Main "1" and "4"

"1"

2.441 - 2.447 mm

Use with crankshaft "R, S"

-

(.0961 -.0963 in.)

"2"

2.435 - 2.441 mm

Use with crankshaft "T, U"

-

(.0958 -.0962 in.)

Lower Main Bearing "2" and "3"

"3"

2.429 - 2.435 mm

Use with crankshaft "R, S"

-

(.0956 -.0958 in.)

"4"

2.423 - 2.429 mm

Use with crankshaft "T, U"

-

(.0953 -.0956 in.)

Bearing Clearances
Main "1, 4"
Crankshaft "R"

.004 -.034 mm (.00015 -.0013 in.)

Crankshaft "S"

.004 -.030 mm (.00015 -.0011 in.)

Crankshaft "T"

.006 -.032 mm (.0002 -.0012 in.)

Crankshaft "U"

.002 -.032 mm (.00007 -. 0012 in.)

Main "2, 3"
Crankshaft "R"

.016 -.046 mm (.0006 -.0018 in.)

Crankshaft "S"

.016 -.042 mm (.00062 -.016 in.)

Crankshaft "T"

.018 -.044 mm (.0007 -.0017 in.)

Crankshaft "U"

.014 -.044 mm (.0005 -.0017 in.)

2007 Dodge Nitro R/T

2007 ENGINE 3.7L - Service Information - Nitro