Chrysler 300M 2002 Service Manual page 1057

9 - 120 ENGINE 3.5L
ROCKER ARM / ADJUSTER ASSEMBLY (Continued)
POSSIBLE NOISE SOURCES
Spongy/soft/aerated lash adjusters.
Missing lash adjuster swivel contact pads.
Intake rocker-to-camshaft bearing journal contact.
Rocker arm bind-up.
Intake rocker arm-to-spark plug tube contact.
Excessive cam end play.
Broken valve spring.
Broken/loose camshaft sprocket bolt.
Incomplete cam lobe machining.
Cracked lash adjuster cartridge body.
POSSIBLE CAUSES
1. Engine oil level—too high or too low. This may
cause aerated oil to enter the adjusters and
cause them to be spongy.
2. Insufficient running time after rebuilding
cylinder head.
3. Air trapped in lash adjuster (after 1 hour run
time).
4. Low oil pressure
5. Oil passage to cylinder head(s) plugged with
debris.
6. Worn valve guide(s).
7. Air injested into oil due to broken or cracked oil
pump pickup tube.
8. Collapsed lash adjuster due to debris injestion.
9. Intake rocker arm roller clevis ear(s) contacting
camshaft bearing journal(s) on side.
*Lash adjusters are serviced with the rocker arms—do not disassemble.
LASH ADJUSTER (TAPPET) NOISE CHART
1. Check and correct engine oil level.
2. Low speed running of up to 1 hour may be required to fully
evacuate trapped air from the valve train system. During this
time, turn engine off and let set for a few minutes before
restarting. Repeat this several times after engine has
reached normal operating temperature.
3. See below:
(a) Check lash adjusters for sponginess while installed in
cylinder head. Depress part of rocker arm over adjuster.
Normal adjusters should feel very firm. Very spongy adjusters
can be bottomed out easily.
(b) Before proceeding, perform Lash Adjuster Bleeding
procedure.
(c) If lash adjuster(s) are still spongy, replace with new
adjuster/rocker arm assembly*.
4. See below:
(a) Check and correct engine oil level.
(b) Check engine oil pressure.
(c) Check for excessive bearing clearance and correct.
(d) Check for worn oil pump.
5. Check cylinder head oil passages and cylinder head
gasket restrictor for blockage. Clean or replace as necessary.
6. Ream guide(s) and replace valve(s) with oversize valves
and seal(s).
7. Inspect pickup tube and replace as necessary.
8. Clean debris from engine and replace lash adjuster/rocker
assembly*.
9. Inspect camshaft end play and all valve train components
for wear. Replace as necessary.
POSSIBLE NOISE MISDIAGNOSIS SOURCES
SRV valve axle chatter.
Exhaust rocker arm-to-cylinder head cover contact.
Piston pin bore fit.
Timing drive hydraulic tensioner tick.
Accessory drive belt deterioration.
Piston-to-bore clearance knock.
Crankshaft bearing noise.
CORRECTION
LH