Engine Cylinder Head; Cylinder Block - Jeep cherokee 2000 Service Manual

9 - 54 2.5L ENGINE
CLEANING AND INSPECTION (Continued)
Inspect the valve stem tip contact surface of each rocker
arm and replace any rocker arm that is deeply pitted.
Inspect each push rod end for excessive wear and
replace as required. If any push rod is excessively
worn because of lack of oil, replace it and inspect the
corresponding hydraulic tappet for excessive wear.
Inspect the push rods for straightness by rolling
them on a flat surface or by shining a light between
the push rod and the flat surface.
A wear pattern along the length of the push rod is
not normal. Inspect the engine cylinder head for
obstruction if this condition exists.

ENGINE CYLINDER HEAD

CLEANING
Thoroughly clean the engine cylinder head and cyl-
inder block mating surfaces. Clean the intake and
exhaust manifold and engine cylinder head mating
surfaces. Remove all gasket material and carbon.
Check to ensure that no coolant or foreign material
has fallen into the tappet bore area.
Remove the carbon deposits from the combustion
chambers and top of the pistons.
INSPECTION
Use a straightedge and feeler gauge to check the
flatness of the engine cylinder head and block mating
surfaces.

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 filter
bypass hole (Fig. 89).
• The front and rear oil galley holes (Fig. 90) (Fig.
91).
• The feed holes for the crankshaft main bearings.
Once the block has been completely cleaned, apply
Mopar Thread Sealant with Teflon to the threads of
the front and rear oil galley plugs. Tighten the plugs
to 41 N·m (30 ft. lbs.) torque.
INSPECTION
Inspect the cylinder bores for signs of scorring, pit-
ting or cracks. If the cylinder bores are scorred or
pitted the cylinder bores will require boreing or hon-
ing to clean them up. Refer to Honing Cylinder Bores
in this Section. If the cylinder bore(s) are cracked the
cylinder block must be replaced.
Inspect the cylinder block to cylinder head mating
surface for flatness and/or pitting.
Fig. 89 Oil Filter Adaptor Hole
1 – FILTER BYPASS HOLE
2 – OIL FILTER ADAPTOR HOLE
Fig. 90 Front Oil Galley Hole
1 – FRONT OIL GALLEY HOLE
Fig. 91 Rear Oil Galley Hole
1 – REAR OIL GALLEY HOLE
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