Engine - Tapping Sound After Engine Warm Up

NUMBER: 07-002-08

GROUP: Cooling

DATE: December 12, 2008

SUBJECT:
Tapping Sound After Engine Warm Up

OVERVIEW:
This Bulletin involves the installation of a serpentine drive belt and a new design idler pulley using a revised belt routing.

MODELS:

2007 - 2008 (KA) Nitro

NOTE:
This bulletin applies to models equipped with the 4.0L engine (sales code EGS).

SYMPTOM/CONDITION:

Some customers may experience a tapping sound from the engine compartment after engine warm up.





PARTS REQUIRED:

DIAGNOSIS:

1. Start engine and allow to idle for 5 minutes to bring accessory drive components to operating temperature.

2. Set HVAC to windshield defrost mode. Set temperature to coldest setting, turn on A/C. While maintaining an engine speed between 1800 - 2000 rpm, listen for tapping sound. If tapping sound is evident, shut engine off. Remove the serpentine drive belt following procedures found in DealerCONNECT > TechCONNECT > Cooling > Accessory Drive > Belt, Serpentine. Do not let the tensioner arm snap back to the free position, damage may occur to the tensioner.

3. Restart engine and listen for tapping sound. Was tapping sound heard?

a. No > Perform Repair Procedure.

b. Yes > This Service Bulletin does not apply, additional diagnosis is required.

REPAIR PROCEDURE:





1. Remove idler pulley # 1 (Fig. 1).

2. Install the new idler pulley and serpentine drive belt using the revised routing (Fig. 1).

POLICY:
Reimbursable within the provisions of the warranty.





TIME ALLOWANCE:





FAILURE CODE:

Disclaimer:
This bulletin is supplied as technical information only and is not an authorization for repair.