Engine - Snapping Noise In Front of Engine Compartment

Number: 92-198A-6A (REVISED)

Section: 6A

Date: JUNE 1992

Corporate Bulletin No.: 276104

ASE No.: A2



Subject:
SNAPPING NOISE IN THE ENGINE COMPARTMENT NEAR FRONT OF ENGINE


Model and Year:
1990-92 BERETTA ONLY



THIS BULLETIN CANCELS AND SUPERSEDES DEALER SERVICE BULLETIN NO. 92-198-6A, DATED MAY 1992. THE MODEL AND YEAR HAVE BEEN CORRECTED. ALL COPIES OF 92-198-6A SHOULD BE DISCARDED.



ENGINE APPLICATIONS:
Quad-4 and Quad OHC (VINs A) (RPOs LGO)

VEHICLE APPLICATIONS:
1990-92 Model Year L



SUBJECT:
Static Discharge between Crankshaft Pulley and Front Cover; Replace Crankshaft Pulley



CONDITION:
A snapping noise in the engine compartment near the front of the engine.


CAUSE:
A static electric charge may be built up in the crankshaft pulley outer ring by serpentine belt friction. If the charge builds to a high enough level, it discharges by arcing to the engine front cover. A snapping sound, similar to a spark plug wire arcing to ground, is created. This static build up is more likely in low humidity conditions and with a serpentine belt which has been in use. The arcing may not be apparent at all in higher humidity conditions and is less likely with a new belt.


CORRECTION:
Replace crankshaft pulley with updated grounded outer ring crankshaft pulley. Refer to Parts Information for correct crankshaft pulley part number.


SERVICE INFORMATION:
Verify the crankshaft pulley is discharging to front cover. Discharge can be seen when engine compartment is relatively dark. DO NOT replace serpentine belt to correct this condition; replacing the belt will only eliminate the condition temporarily

Refer to Section 6A7 of the service manual for crankshaft pulley replacement procedure.



PARTS INFORMATION:
Vehicles built after February 1992 will have the updated crankshaft pulley. Refer to date on the label on the end of the driver side door.

New Pulley
Part Number Diameter Application
24573264 Small 1990-91 (VIN A)
1992 Quad 4 (VIN A - W41)

24573015 Large All 1992 (VIN A)

Parts are currently available from GMSPO.

WARRANTY INFORMATION:
Labor Time Operation Number:
J0700

Labor Time Allowance:
Refer to current Labor Time Guide for labor time allowance.