Dodge Nitro. Manual — part 122

Fig. 215: Piston & Connecting Rod Positioning
Courtesy of CHRYSLER LLC

8. The oil squirt hole on connecting rod faces the major thrust side of the cylinder bore. See Fig. 215.

9. Tap the piston down in cylinder bore, using a hammer handle. At the same time, guide connecting rod

into position on connecting rod journal.

10. Install the rod caps. Install cleaned and inspected connecting rod bolts and tighten to 27 N.m (20 ft. lbs.)

Plus 1/4 turn.

11. Install the cylinder head(s). See INSTALLATION.

12. Install the oil pan. See INSTALLATION.

RING - PISTON

1 - MAJOR THRUST SIDE OF PISTON
2 - OIL SQUIRT HOLE

CAUTION: View of connecting rod oil squirt hole is from the front of the engine.

NOTE:

Make sure the rod bearings are seated with the oil squirt hole aligned.

NOTE:

Connecting rod bolts must be lubricated with clean engine oil.

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro

DESCRIPTION

RING - PISTON

Fig. 216: Piston Rings
Courtesy of CHRYSLER LLC

The piston rings include a moly-filled top ring with a symmetric barrel face. The intermediate piston ring is of
the standard chrome design OR Micro-Napier design. The Micro-Napier design has a reduced "hook" on the
running face, removes the need for chroming and improves oil economy. The oil control package consists of
two steel rails and an expander spacer. See Fig. 216.

STANDARD PROCEDURE

1 - TOP PISTON RING
2 - CHROME INTERMEDIATE PISTON RING
3 - MICRO-NAPIER INTERMEDIATE PISTON RING
4 - OIL CONTROL RINGS
5 - SPACER

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro

PISTON RING FITTING

Fig. 217: Checking Piston Rings Gap
Courtesy of CHRYSLER LLC

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 in.) from bottom of
cylinder bore. Check gap with feeler gauge. See Fig. 217. For clearance specifications, see
SPECIFICATIONS.

1 - FEELER GAUGE

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro

Fig. 218: Checking Piston Ring To Groove Clearance
Courtesy of CHRYSLER LLC

2. Check piston ring to groove clearance: See Fig. 218. For clearance specifications, see

SPECIFICATIONS.

REMOVAL

RING - PISTON

1 - FEELER GAUGE

2007 Dodge Nitro R/T

2007 ENGINE 4.0L - Service Information - Nitro