MECHANICAL
4. Contamination in fuel system.
4. Clean system and replace fuel
filter.
CONDITION
POSSIBLE CAUSES
CORRECTION
NOISY VALVES
1. High or low oil level in
crankcase.
1. Check and correct engine oil
level.
2. Thin or diluted oil.
2. Change oil to correct viscosity.
3. Thick oil
3. (a) Change engine oil and filter.
(b) Run engine to operating
temperature.
(c) Change engine oil and filter
again.
4. Low oil pressure.
4. Check and correct engine oil
pressure problem.
5. Dirt in hydraulic lifters/lash
adjusters.
5. Replace hydraulic lifters/lash
adjusters.
6. Worn rocker arms.
6. Inspect oil supply to rocker
arms.
7. Worn hydraulic lifters/lash
adjusters.
7. Replace hydraulic lifters/lash
adjusters.
8. Worn valve guides.
8. Replace cylinder head
assembly.
9. Excessive runout of valve seats
on valve faces.
9. Grind valve seats and valves.
CONNECTING ROD NOISE
1. Insufficient oil supply.
1. Check engine oil level.
2. Low oil pressure.
2. Check engine oil level. Inspect
oil pump relief valve and spring.
3. Thin or diluted oil.
3. Change oil to correct viscosity.
4. Thick oil
4. (a) Change engine oil and filter.
(b) Run engine to operating
temperature.
(c) Change engine oil and filter
again.
5. Excessive bearing clearance.
5. Measure bearings for correct
clearance. Repair as necessary.
6. Connecting rod journal out-of-
round.
6. Replace crankshaft or grind
surface.
7. Misaligned connecting rods.
7. Replace bent connecting rods.
MAIN BEARING NOISE
1. Insufficient oil supply.
1. Check engine oil level.
2. Low oil pressure.
2. Check engine oil level. Inspect
oil pump relief valve and spring.
3. Thin or diluted oil.
3. Change oil to correct viscosity.
4. Thick oil
4. (a) Change engine oil and filter.
2010 Jeep Wrangler Sport
2010 ENGINE 3.8L - Service Information - Wrangler
viernes, 1 de octubre de 2021 05:18:29 p. m.
Page 4
© 2011 Mitchell Repair Information Company, LLC.
