Jeep cherokee 2000 Service Manual page 761

XJ
DIAGNOSIS AND TESTING (Continued)
CONDITION
CONNECTING ROD NOISE
MAIN BEARING NOISE
POSSIBLE CAUSES
4. Dirt in tappets/lash adjusters
5. Bent push rod(s)
6. Worn rocker arms
7. Worn tappets/lash adjusters
8. Worn valve guides
9. Excessive runout of valve seats
or valve faces
1. Insufficient oil supply
2. Low oil pressure
3. Thin or diluted oil
4. Excessive connecting rod
bearing clearance
5. Connecting rod journal out of
round
6. Misaligned connecting rods
1. Insufficient oil supply
2. Low oil pressure
3. Thin or diluted oil
4. Excessive main bearing
clearance
5. Excessive end play
6. Crankshaft main journal out of
round or worn
7. Loose flywheel or torque
converter
4.0L ENGINE
CORRECTION
4. Clean/replace hydraulic
tappets/lash adjusters
5. Install new push rods
6. Inspect oil supply to rocker arms
and replace worn arms as needed
7. Install new hydraulic tappets/lash
adjusters
8. Inspect all valve guides and
replace as necessary
9. Grind valves and seats
1. Check engine oil level. (Refer to
group 0, Lubrication and
Maintenance)
2. Check engine oil level. If ok,
Perform oil pressure test. Refer to
this group for engine oil pressure
test/specifications
3. Change oil to correct viscosity.
Refer to this group for correct
procedure/engine oil specifications
Measure bearings for correct
clearance with plasti-gage. Repair
as necessary
5. Replace crankshaft or grind
journals
6. Replace bent connecting rods
1. Check engine oil level. (Refer to
group 0, Lubrication and
Maintenance)
2. Check engine oil level. If ok,
Perform oil pressure test. Refer to
this group for engine oil pressure
test/specifications
3. Change oil to correct viscosity.
Refer to this group for correct
procedure/engine oil specifications
4. Measure bearings for correct
clearance. Repair as necessary
5. Check crankshaft thrust bearing
for excessive wear on flanges
6. Grind journals or replace
crankshaft
7. Inspect crankshaft, flexplate/
flywheel and bolts for damage.
Tighten to correct torque
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