Engine Noise Under Load - Chevrolet 5.7L Corvette 2004 Shop Manual

Loose or damaged flywheel
Oil pump screen loose, damaged or restricted
Excessive piston-to-cylinder bore clearance
Excessive piston pin-to-bore clearance
Excessive connecting rod bearing clearance
Excessive crankshaft bearing clearance
Incorrect piston, piston pin and connecting rod
installation
Pistons must be installed with the mark or dimple on
the top of the piston facing the front of the engine.
Piston pins must be centered in the connecting rod
pin bore.

ENGINE NOISE UNDER LOAD

Engine Noise Under Load
Cause
IMPORTANT:
A cold piston knock which disappears in 1.5 minutes should be considered acceptable. A cold
engine knock usually disappears when the specific cylinder's secondary ignition circuit is grounded
out during diagnosis.
A low rumble/knocking may indicate a crankshaft or piston, lower engine concern.
Low oil pressure
flywheel.
Repair or replace as required.
Repair or replace the flywheel.
Inspect the oil pump screen.
Repair or replace as required.
Inspect the piston and cylinder bore.
Repair as required.
Inspect the piston, pin, and connecting rod.
Replace the piston, and pin as an assembly,
as required.
Inspect the following components, and repair as
required:
The connecting rod bearings
The connecting rods
The crankshaft
The crankshaft journals
Inspect the following components, and repair as
required:
The crankshaft bearings
The crankshaft journals
Verify the pistons, piston pins and
connecting rods are installed correctly. Refer
to Piston, Connecting Rod, and Bearing
Installation .
Repair as required.
Perform an oil pressure test. Refer to Oil Pressure Diagnosis and
Testing .
Repair or replace as required.
Correction