Dodge 2000 DURANGO Service Manual page 585

9 - 76 4.7L ENGINE
CLEANING AND INSPECTION (Continued)
PISTON AND CONNECTING ROD
CLEANING
CAUTION: DO NOT use a wire wheel or other abra-
sive cleaning devise to clean the pistons or con-
necting rods. The pistons have a Moly coating, this
coating must not be damaged.
(1) Using a suitable cleaning solvent clean the pis-
tons in warm water and towel dry.
(2) Use a wood or plastic scraper to clean the ring
land grooves.
CAUTION: DO NOT remove the piston pin from the
piston and connecting rod assembly.
INSPECTION
Check the crankshaft connecting rod journal for
excessive wear, taper and scoring.
Check the pistons for taper and elliptical shape
before they are fitted into the cylinder bore.
Replace any piston and connecting rod not meeting
the specifications.
OIL PAN
CLEANING
(1) Clean oil pan in solvent and wipe dry with a
clean cloth.
(2) Clean the oil pan gasket surface. DO NOT use
a grinder wheel or other abrasive tool to clean seal-
ing surface.
(3) Clean oil screen and tube thoroughly in clean
solvent.
INSPECTION
(1) Inspect oil drain plug and plug hole for
stripped or damaged threads. Repair as necessary.
(2) Inspect the oil pan mounting flange for bends
or distortion. Straighten flange, if necessary.
OIL PUMP
CLEANING
(1) Wash all parts in a suitable solvent.
INSPECTION
CAUTION: Oil pump pressure relief valve and
spring should not be removed from the oil pump. If
the these components are disassembled andør
removed from the pump the entire oil pump assem-
bly must be replaced.
(1) Clean all parts thoroughly. Mating surface of
the oil pump housing should be smooth. If the pump
cover is scratched or grooved the oil pump assembly
should be replaced.
(2) Lay a straight edge across the pump cover sur-
face (Fig. 137). If a 0.025 mm (0.001 in.) feeler gauge
can be inserted between the cover and the straight
edge the oil pump assembly should be replaced.
(3) Measure the thickness of the outer rotor (Fig.
138). If the outer rotor thickness measures at 12.005
mm (0.400 in.) or less the oil pump assembly must be
replaced.
(4) Measure the diameter of the outer rotor. If the
outer rotor diameter measures at 85.925 mm (0.400
in.) or less the oil pump assembly must be replaced.
(5) Measure the thickness of the inner rotor (Fig.
139). If the inner rotor thickness measures at 12.005
mm (0.400 in.) or less then the oil pump assembly
must be replaced.
(6) Slide outer rotor into the body of the oil pump.
Press the outer rotor to one side of the oil pump body
and measure clearance between the outer rotor and
the body (Fig. 140). If the measurement is 0.47mm
(0.0186 in.) or more the oil pump assembly must be
replaced.
(7) Install the inner rotor in the into the oil pump
body. Measure the clearance between the inner and
outer rotors (Fig. 141). If the clearance between the
rotors is .150 mm (0.006 in.) or more the oil pump
assembly must be replaced.
(8) Place a straight edge across the body of the oil
pump (between the bolt holes), if a feeler gauge of
.095 mm (0.0038 in.) or greater can be inserted
between the straightedge and the rotors, the pump
must be replaced (Fig. 142).
NOTE: 4.7 Oil pump is released as an assembly.
There are no DaimlerChrysler part numbers for Sub-
Assembly components. In the event the oil pump is
not functioning or out of specification it must be
replaced as an assembly.
CYLINDER BLOCK
CLEANING
Thoroughly clean the oil pan and engine block gas-
ket surfaces.
Use compressed air to clean out:
• The galley at the oil filter adaptor hole.
• The front and rear oil galley holes.
• The feed holes for the crankshaft main bearings.
Once the block has been completely cleaned, apply
Loctite PST pipe sealant with Teflon 592 to the
threads of the front and rear oil galley plugs. Tighten
the plugs to 34 N·m (25 ft. lbs.) torque.
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