Upper Engine Noise, Regardless Of Engine Speed - Chevrolet 5.7L Corvette 2004 Shop Manual

Engine Noise on Start-Up, but Only Lasting a Few Seconds
Cause
Incorrect oil filter without anti-drainback
feature
Incorrect oil viscosity
High valve lifter leak down rate
Worn crankshaft thrust bearing
Damaged or faulty oil filter by-pass valve

UPPER ENGINE NOISE, REGARDLESS OF ENGINE SPEED

Upper Engine Noise, Regardless of Engine Speed
Cause
Low oil pressure
Loose and/or worn valve rocker arm
attachments
Worn or damaged valve rocker arm
Bent or damaged push rod
Improper lubrication to the valve
rocker arms
Install the correct oil filter.
1. Drain the oil.
2. Install the correct viscosity oil.
Replace the lifters as required.
1. Check the crankshaft end play.
2. Inspect the thrust bearing and crankshaft.
3. Repair or replace as required.
Inspect the oil filter by-pass valve for proper
operation.
Repair or replace as required.
Perform an oil pressure test. Refer to Oil Pressure
Diagnosis and Testing .
Repair or replace as required.
Inspect the valve rocker arm, bolt, and pedestal.
Repair or replace as required.
Inspect the rocker arm for wear or missing needle bearings.
Replace the valve rocker arms as required.
Inspect the following components, and replace as required:
The valve rocker arm
The valve push rod
The valve lifter
The valve lifter guide
The piston
Inspect the top of the pistons for valve contact. If the top of the
piston shows valve contact, replace the piston and pin assembly.
Inspect the following components, and repair or replace as
required:
Restricted oil filter
Correction
Correction