ENGINE NOISE UNDER LOAD
Engine Noise Under Load
flywheel.
z
Repair or replace as required.
Loose or damaged flywheel
Repair or replace the flywheel.
Oil pump screen loose, damaged or restricted
z
Inspect the oil pump screen.
z
Repair or replace as required.
Excessive piston-to-cylinder bore clearance
z
Inspect the piston and cylinder bore.
z
Repair as required.
Excessive piston pin-to-bore clearance
z
Inspect the piston, pin, and connecting rod.
z
Replace the piston, and pin as an assembly,
as required.
Excessive connecting rod bearing clearance
Inspect the following components, and repair as
required:
z
The connecting rod bearings
z
The connecting rods
z
The crankshaft
z
The crankshaft journals
Excessive crankshaft bearing clearance
Inspect the following components, and repair as
required:
z
The crankshaft bearings
z
The crankshaft journals
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.
z
Verify the pistons, piston pins and
connecting rods are installed correctly. Refer
to
Piston, Connecting Rod, and Bearing
Installation
.
z
Repair as required.
Cause
Correction
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
z
Perform an oil pressure test. Refer to
Oil Pressure Diagnosis and
Testing
.
z
Repair or replace as required.
2004 Chevrolet Corvette
2004 ENGINE PERFORMANCE Engine Mechanical (Introduction) - 5.7L - Corvette
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December-24-07 10:50:09 AM
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