Engine - Metallic Knock/Noise on Start Up

Models


1983-1984 Conquest, Ram 50 With 2.6L Engine


Subject


Start Up Knock


Index


ENGINE

Date

July 22, 1985


No.


09-09-85

P-2599
SYMPTOM/CONDITION

Metallic noise or knock sound for 1-3 seconds after engine start up, on vehicles that have not been operated for a period of four hours or longer.

NOTE: THIS START UP NOISE IS NOT DETRIMENTAL TO ENGINE RELIABILITY. HOWEVER, THE FOLLOWING REPAIR CAN BE PERFORMED TO ELIMINATE THIS NOISE.

PARTS REQUIRED

1 Dampener PN MD084945

REPAIR PROCEDURE

NOTE: THE DAMPENER IS INSTALLED IN ALL ENGINES BUILT AFTER OCTOBER, 1984.

The start up knock is caused by the timing chain tensioner relaxing and expelling the engine oil from the tensioner oil pressure cavity. The rubber dampener, PN MD084945, is placed inside the tensioner spring to prevent excessive chain relaxation and reduces the volume of oil required to fill the tensioner cavity. The result is quicker oil pressurization and elimination of the start up knock.

1. Using the appropriate service manual, disassemble the engine far enough to remove the timing chain tensioner and spring.

FIGURE 1 - Tensioner Spring:

2. Insert the rubber dampener, PN MD084945, inside the tensioner spring (Figure 1).
3. Reinstall the spring and tensioner in the oil pump.

4. Reassemble the engine.

5. Road test the car and check for leaks.


POLICY: Reimbursable within the provisions of the warranty


TIME ALLOWANCE: Refer to Labor Operation Time Schedule for operation and time.