Engine - Low End Knock Noise
Article No. 85-9-9NOISE - ENGINE KNOCK (2.3L EFI TURBO) - AIR CONDITIONING BELT DRIVEN FROM THE WATER PUMP PULLEY
FORD 1985 THUNDERBIRD
LINCOLN-MERCURY 1985 COUGAR
CALIBRATIONS: 5-05E
WARNING: This modification is authorized only for the listed engines. Performing this modification on other engine calibrations is unauthorized and could create liability under applicable federal or local laws.
A "low end" knock noise on vehicles equipped with a manual transmission and air conditioning may be caused by the A/C belt driven off the crankshaft pulley creating a side load on the front main bearing.
The condition can be diagnosed by removing the A/C belt and running the engine at (hot) idle speed. If the
knock noise is eliminated, service the condition by revising the A/C drive belt to drive off the water pump pulley instead of the crankshaft pulley.
1. Remove the water pump pulley, A/C belt and idler pulley assembly and discard.
Figure 8 - Water Pump Pulley and A/C Belt:
2. Install a new water pump pulley and A/C belt using part numbers E5ZZ-8509-C and E5PZ-8620-D (Figure 8).
3. Tighten the belt to specification 120-160 lbs.
PART NUMBER PART NAME CLASS
E5ZZ-8509-C Pulley - Water Pump C
E5PZ-8620-D Belt - A/C A
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP862OA85
TIME: 0.5 Hr. DLR. CODING; Basic Part No. DRIVE - Code: P8